refs: https://github.com/TryGhost/Toolbox/issues/245
- Upload, updateMembersEmail, validateMembersEmailUpdate & disconnectStripeConnectIntegration were all missing serializers
- Upload is an as-is response, same as download
- updateMembersEmail, validateMembersEmailUpdate & disconnectStripeConnectIntegration are all passthroughs with no response
- With the upcoming refactor we want to have all the serializers defined explicitly
- This will allow us to change the default behaviour
- Updated the file based tests to prove the body doesn't change
- Tests were added to cover updateMembersEmail, validateMembersEmailUpdate & disconnectStripeConnectIntegration in 68c1bc0285
- split out the two tests that use files, as the new framework doesn't support this yet
- convert the 3 existing tests for the settings endpoint to use the new framework
- introduced a new pattern of using a function to generate a matching array, so that we can do extra stuff
- in this case, just one of the items needed a matcher for the value, which results in slightly weird code
- wrapping in a function gives us somewhere to do this and leave a comment
