Bump crossbeam-channel from 0.5.11 to 0.5.12

Bumps [crossbeam-channel](https://github.com/crossbeam-rs/crossbeam) from 0.5.11 to 0.5.12.
- [Release notes](https://github.com/crossbeam-rs/crossbeam/releases)
- [Changelog](https://github.com/crossbeam-rs/crossbeam/blob/master/CHANGELOG.md)
- [Commits](https://github.com/crossbeam-rs/crossbeam/compare/crossbeam-channel-0.5.11...crossbeam-channel-0.5.12)

---
updated-dependencies:
- dependency-name: crossbeam-channel
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Cargo.lock

@@ -321,9 +321,9 @@ dependencies = [
 
 [[package]]
 name = "crossbeam-channel"
-version = "0.5.11"
+version = "0.5.12"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "176dc175b78f56c0f321911d9c8eb2b77a78a4860b9c19db83835fea1a46649b"
+checksum = "ab3db02a9c5b5121e1e42fbdb1aeb65f5e02624cc58c43f2884c6ccac0b82f95"
 dependencies = [
  "crossbeam-utils",
 ]