GH1089Fix nightly for pandas 3.0.0 due to future warnings

[loicdiridollou]

• Closes Fix pandas nightly test build and migrate tests over new framework #1089
• Tests added: Please use assert_type() to assert the type of any return value

[Dr-Irv]

/pandas_nightly

[Dr-Irv]

The test to do the nightly test from here didn't work. See https://github.com/pandas-dev/pandas-stubs/actions/runs/13394741704/job/37410799701#step:3:64

Can you look into that? If it's too hard, let me know, and I'll approve this PR.

[loicdiridollou]

/pandas_nightly

[loicdiridollou]

@Dr-Irv I understand the error, the initial issue with the comment commands was that it would checkout the main branch and not the one we want to merge so I fixed this. Now the issue is that it is looking for the branch in the pandas-stubs repo although in the current setting the branch in on my personal repo (loicdiridollou/pandas-stubs).
I will fix this in a separate PR, just need to test it on a dummy repo on my end so would be preferable to merge this one (I tested the changes locally running poetry run poe pytest --nightly and it was good.

[Dr-Irv]

thanks @loicdiridollou