feat: mark IgnoreNulls and RespectNulls as unsupported on postgres and mysql

[NickCrews]

Fixes #6376

• on postgres, using either IGNORE NULLS or RESPECT NULLS errors
• on mySQL, you are allowed to use RESPECT NULLS, only using IGNORE NULLS results in an error

There are probably other dialects that also need this change, but these are the ones I've discovered so far.

[geooo109]

@NickCrews thanks for the PR, it seems that this is the same handling as the SQLite.
Can you also add tests for this? (after fixing the typing)

[NickCrews]

There are no tests for the sqlite version that I can use as a template. Should I add tests to each individual test_{dialect}.py file? I think it would be better if there was a central test_ignore_nulls() function that was parameterized by the dialect

I also can't reproduce the ruff-format linting error from CI. When I try to repro that using the steps in the GHA workflow, the ruff-format check passes. I'm still getting ruff==0.7.2. I am on macos, not linux, so maybe there is some other environment mismatch? I wish you would use uv and a lockfile in this project, it would be way faster and easier and familiar for me and probably other python devs.

[geooo109]

Something similar with the unsupported here: d86a114#diff-3d52365bb42988855f191716c88abe51e577bd1122e2a977a5d967281f1b17f9

[georgesittas]

I also can't reproduce the ruff-format linting error from CI. When I try to repro that using the steps in the GHA workflow, the ruff-format check passes. I'm still getting ruff==0.7.2. I am on macos, not linux, so maybe there is some other environment mismatch? I wish you would use uv and a lockfile in this project, it would be way faster and easier and familiar for me and probably other python devs.

If you dev. in a fresh venv environment and run make install-dev you should get matching dependency versions to fix this issue.

[geooo109]

@NickCrews let me get this to the finish line

[NickCrews]

Something similar with the unsupported here: d86a114#diff-3d52365bb42988855f191716c88abe51e577bd1122e2a977a5d967281f1b17f9

Oops, wow, sorry, I totally forgot about #5185. If I had, then I would have had a lot better sense of what to do.

@NickCrews let me get this to the finish line

Thank you very much!

If you dev. in a fresh venv environment and run make install-dev you should get matching dependency versions to fix this issue.

Thanks!