CLN: tests/extension/json/test_json.py typefix
The error is due to the fact that the builtins.staticmethod type defined in extension.base.base.BaseExtensionTests does not match the function type in extension.json.test_json.BaseJSON. I don't see a possibility for a proper type hint fix without changing the structure of the code. One way would be to replace the call of staticmethod by function definitions that call the corresponding methods.
Here I propose an easier suppression of the error using type: Any.
What do you think?

- [ ] xref #28926
- [ ] tests added / passed
- [ ] passes `black pandas`
- [ ] passes `git diff upstream/master -u -- "*.py" | flake8 --diff`
- [ ] whatsnew entry

@lukasbk can you rebase Hello @lukasbk! Thanks for updating this PR. We checked the lines you've touched for [PEP 8](https://www.python.org/dev/peps/pep-0008) issues, and found:























There are currently no PEP 8 issues detected in this Pull Request. Cheers! :beers: 

##### Comment last updated at 2019-12-15 18:57:28 UTC @lukasbk looks like a merge conflict; can you fix up and address comments? looks ok to me. I am bit concerned that we are now changing back to using ``tm`` as we *do* want the ability to override on these tests, but I guess that mypy will check this now. can you rebase @lukasbk can you fix up the merge conflict? I think we can get this in if so @lukasbk the CI didn't pass, and this is conflicting again.

Do you mind merging master again, making sure the CI passes, and pinging us to get this merged quickly after that please? Thanks! @lukasbk can you fix up merge conflict? I think this was close closing as stale. cc @SaturnFromTitan 