Debug azure-storage-blob test failures

[dstansby]

Hopefully get to the bottom of what's going on in #2122...

I'm going to start by bisecting what version of azure-storage-blob first had an issue. For reference, changelog here: https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/storage/azure-storage-blob/CHANGELOG.md

The highest version that still works is 2.21.0, so I've set that as the pin here.

TODO:

• Add unit tests and/or doctests in docstrings
• Add docstrings and API docs for any new/modified user-facing classes and functions
• New/modified features documented in docs/tutorial.rst
• Changes documented in docs/release.rst
• GitHub Actions have all passed
• Test coverage is 100% (Codecov passes)

[dstansby]

Well it's 1.22.0 that the error first shows up in. I suspect it will end up being something in this huge commit that's causing the issue... Azure/azure-sdk-for-python@cb47de5

[jhamman]

How strongly do we feel about fixing this? There is also support for azure blob storage via fsspec (https://github.com/fsspec/adlfs) so this class is now duplicative. Its also been deprecated and will be removed in 3.0. So maybe we just keep the pin in place?

[joshmoore]

I could definitely live with a pin. Going back to #781 having a group that champions these individual stores would be my overall preference (knowing I definitely don't do enough testing or have the experience needed)

[dstansby]

azure-storage-blob isn't specified as an optional dependency anywhere, so there's nowhere to pin it apart from in the test requirements file. I've updated this PR to have the highest pin that still works. Is it worth adding it as an optional dependency to the package with an upper pin?

[dstansby]

The actual version bump to 2.21.0 happened in #2129 - I'll close this, and open an issue if anyone wants to try and debug azure-storage-blob 2.22.0...