What's Changed
* Add v1.56.4 support by henribru in https://github.com/henribru/googleapis-common-protos-stubs/pull/7
* [Loosen requirement versions](https://github.com/henribru/googleapis-common-protos-stubs/commit/831249d777220288b0a19bb7ee2a265f100e497f)
* [Update classifier](https://github.com/henribru/googleapis-common-protos-stubs/commit/d589b1c32a56d5f3386d693d331020425de203a8)
**Full Changelog**: https://github.com/henribru/googleapis-common-protos-stubs/compare/v2.0.0...v2.1.0