Add regression tests

[phofl]

Search for a minimal example and the confirmation that it's fixed. Add the test then

• [ ] https://github.com/pandas-dev/pandas/issues/33331
• [ ] https://github.com/pandas-dev/pandas/issues/37480
• [ ] https://github.com/pandas-dev/pandas/issues/43996
• [ ] https://github.com/pandas-dev/pandas/issues/51500
• [ ] https://github.com/pandas-dev/pandas/issues/25548
• [ ] https://github.com/pandas-dev/pandas/issues/25298
• [ ] https://github.com/pandas-dev/pandas/issues/33457
• [x] https://github.com/pandas-dev/pandas/issues/29707
• [x] https://github.com/pandas-dev/pandas/issues/54347

[MovsisyanM]

Working on .loc assignment tests

[LuckIlNe]

Working on #51500 tests

[KevorkSulahian]

will take a go at #37480