community/py3-apipkg: upgrade to 2.1.0

As result of below described changelog = enabled tests back.

https://github.com/pytest-dev/apipkg/blob/v2.1.0/CHANGELOG#L1-L23

2.1.0

• fix race condition for import of modules using apipkg.initpkg in Python 3.3+ by updating existing modules in-place rather than replacing in sys.modules with an apipkg.ApiModule instances. This race condition exists for import statements (and import) in Python 3.3+ where sys.modules is checked before obtaining an import lock, and for importlib.import_module in Python 3.11+ for the same reason.

2.0.1

• fix race conditions for attribute creation

2.0.0

• also transfer spec attribute
• make py.test hack more specific to avoid hiding real errors
• switch from Travis CI to GitHub Actions
• modernize package build
• reformat code with black