doc: contributing: fix azure CI link

This one doesn't work in markdown here for some reason

[ci skip]

CONTRIBUTING.md

@@ -22,7 +22,7 @@ $toc$
 | Github                  | [simonmichael/hledger](https://github.com/simonmichael/hledger) (shortcut: code.hledger.org), [forks](http://forked.yannick.io/simonmichael/hledger) <br> [commits](http://github.com/simonmichael/hledger/commits), <!-- [unreleased commits](https://github.com/simonmichael/hledger/compare/0.23...master), [release branch commits](https://github.com/simonmichael/hledger/compare/master...0.23), --> [COMMITS!](http://starlogs.net/#simonmichael/hledger) <br> [open bugs](http://bugs.hledger.org), [open wishes](http://wishes.hledger.org), [open unknowns](https://github.com/simonmichael/hledger/issues?utf8=✓&q=is%3Aissue%20is%3Aopen%20-label%3A%22A%20BUG%22%20-label%3A%22A%20WISH%22%20), [open pull requests](http://prs.hledger.org), [all issues](https://github.com/simonmichael/hledger/issues?q=) <br> [issues with bounty tag](https://github.com/simonmichael/hledger/issues?q=label:bounty), [bountysource bounties](https://github.com/simonmichael/hledger/issues?q=%22Add%20to%20the%20bounty%20at%20Bountysource%22%20OR%20%22claim%20the%20bounty%20on%20Bountysource%22%20OR%20%22bounty%20on%20this%20issue%20has%20been%20claimed%20at%20Bountysource%22%20), [codemill bounties](https://github.com/simonmichael/hledger/issues?q=codemill), [codefund bounties](https://github.com/simonmichael/hledger/issues?utf8=✓&q=codefund) <br> [stars.hledger.org](http://stars.hledger.org):  <a class="github-button" href="https://github.com/simonmichael/hledger" data-icon="octicon-star" data-count-href="/simonmichael/hledger/stargazers" data-count-api="/repos/simonmichael/hledger#stargazers_count" data-count-aria-label="# stargazers on GitHub" aria-label="Star simonmichael/hledger on GitHub"></a> our rank among ~30k starred haskell projects:<br>2016: ->#71, 2017: ->#54, 2018 ->#53) <br> [github projects](https://github.com/simonmichael/hledger/projects), [waffle.io planning board](https://waffle.io/simonmichael/hledger?source=simonmichael%2Fhledger) <br> [<img width=520 height=170 title="..." src="https://graphs.waffle.io/simonmichael/hledger/throughput.svg">](https://waffle.io/simonmichael/hledger/metrics) |
 | Travis CI               | [![...](https://api.travis-ci.org/simonmichael/hledger.svg?branch=master)](https://travis-ci.org/simonmichael/hledger/builds)
 | Appveyor CI             | [![...](https://ci.appveyor.com/api/projects/status/5vejw0w5n5igdr42?svg=true)](https://ci.appveyor.com/project/simonmichael/hledger/history) 
-| Azure CI                | [![...](https://dev.azure.com/simonmic/hledger/_apis/build/status/simonmichael.hledger?branchName=master)](https://dev.azure.com/simonmic/hledger/_build) 
+| Azure CI                | <a href="https://dev.azure.com/simonmic/hledger/_build"><img src="https://dev.azure.com/simonmic/hledger/_apis/build/status/simonmichael.hledger?branchName=master" alt="..."></a>
 | Hackage                 | <a name=hackage></a>packages: [hledger-lib](http://hackage.haskell.org/package/hledger-lib), [hledger](http://hackage.haskell.org/package/hledger), [hledger-ui](http://hackage.haskell.org/package/hledger-ui), [hledger-web](http://hackage.haskell.org/package/hledger-web), [hledger-api](http://hackage.haskell.org/package/hledger-api), [hledger-diff](http://hackage.haskell.org/package/hledger-diff), [hledger-iadd](http://hackage.haskell.org/package/hledger-iadd), [hledger-interest](http://hackage.haskell.org/package/hledger-interest), [hledger-irr](http://hackage.haskell.org/package/hledger-irr), [\*hledger\*](http://hackage.haskell.org/packages/search?terms=hledger) <!-- [![...](https://img.shields.io/hackage/v/hledger.svg?label=current+release)](http://hackage.haskell.org/package/hledger) --> <br> diffs: [hledger-lib](http://hdiff.luite.com/cgit/hledger-lib/diff), [hledger](http://hdiff.luite.com/cgit/hledger/diff), [hledger-ui](http://hdiff.luite.com/cgit/hledger-ui/diff), [hledger-web](http://hdiff.luite.com/cgit/hledger-web/diff), [hledger-api](http://hdiff.luite.com/cgit/hledger-api/diff) <br> build status: [hledger-lib](http://matrix.hackage.haskell.org/package/hledger-lib), [hledger](http://matrix.hackage.haskell.org/package/hledger), [hledger-ui](http://matrix.hackage.haskell.org/package/hledger-ui), [hledger-web](http://matrix.hackage.haskell.org/package/hledger-web), [hledger-api](http://matrix.hackage.haskell.org/package/hledger-api) <br> reverse deps: [hledger-lib](http://packdeps.haskellers.com/reverse/hledger-lib), [hledger](http://packdeps.haskellers.com/reverse/hledger), [hledger-ui](http://packdeps.haskellers.com/reverse/hledger-ui), [hledger-web](http://packdeps.haskellers.com/reverse/hledger-web), [hledger-api](http://packdeps.haskellers.com/reverse/hledger-api) <br> bounds status:<br>[![...](https://img.shields.io/hackage-deps/v/hledger-lib.svg?label=hledger-lib+bounds)](http://packdeps.haskellers.com/feed?needle=hledger-lib) [![...](https://img.shields.io/hackage-deps/v/hledger.svg?label=hledger+bounds)](http://packdeps.haskellers.com/feed?needle=hledger) [![...](https://img.shields.io/hackage-deps/v/hledger-ui.svg?label=hledger-ui+bounds)](http://packdeps.haskellers.com/feed?needle=hledger-ui) [![...](https://img.shields.io/hackage-deps/v/hledger-web.svg?label=hledger-web+bounds)](http://packdeps.haskellers.com/feed?needle=hledger-web) [![...](https://img.shields.io/hackage-deps/v/hledger-api.svg?label=hledger-api+bounds)](http://packdeps.haskellers.com/feed?needle=hledger-api) |
 | Stackage                | [build-constraints.yaml](https://github.com/fpco/stackage/blob/master/build-constraints.yaml) <br> [open hledger-related issues](https://github.com/fpco/stackage/search?q=hledger+is%3Aopen&type=Issues) <br> packages: [hledger-lib](https://www.stackage.org/package/hledger-lib), [hledger](https://www.stackage.org/package/hledger), [hledger-ui](https://www.stackage.org/package/hledger-ui), [hledger-web](https://www.stackage.org/package/hledger-web), [hledger-api](https://www.stackage.org/package/hledger-api)<br> versions: [hledger-lib](https://www.stackage.org/package/hledger-lib/snapshots), [hledger](https://www.stackage.org/package/hledger/snapshots), [hledger-ui](https://www.stackage.org/package/hledger-ui/snapshots), [hledger-web](https://www.stackage.org/package/hledger-web/snapshots), [hledger-api](https://www.stackage.org/package/hledger-api/snapshots) <br>[![...](https://repology.org/badge/version-for-repo/stackage_nighly/hledger.svg)](https://repology.org/metapackage/hledger)|
 | Repology                | [quick hledger packaging status](https://repology.org/metapackage/hledger/badges), [detailed \*hledger\* packaging status](https://repology.org/metapackages/?search=hledger) <br>[![...](https://repology.org/badge/tiny-repos/hledger.svg)](https://repology.org/metapackage/hledger)