Release v0.2.1 to fix Invalid distribution metadata: license-expression

[grische]

While trying to mirror the get-deps package into a local cache, I noticed that the current version v0.2.0 on pypi uses invalid package metadata and hence cannot be uploaded using twine:

ERROR    InvalidDistribution: Invalid distribution metadata: license-expression 
         introduced in metadata version 2.4, not 2.1           

This was fixed in commit 9a0f53e but we never saw a release for it.

@oprypin it would be great if you could you make a release for it and push it to pypi.

[oprypin]

I actually don't have control of these repos, MkDocs is being held hostage for 2 years now

• Maintainership mkdocs#3677