gh-149738: Fix segmentation fault bug in sqllite3

[sepehr-rs]

Fixes #149738.

>>> import sqlite3
>>> db = sqlite3.connect(":memory:")
>>> del db.row_factory
>>> db.execute("test")
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
    db.execute("test")
    ~~~~~~~~~~^^^^^^^^
sqlite3.OperationalError: near "test": syntax error
>>> 

• Issue: deleting sqlite3 row_factory causes segfault #149738

[picnixz]

We need tests and check what happens on the created connection after deletion (check that there is still a row factory on the newly created cursor)

[sepehr-rs]

Thanks for your comment and review, @picnixz!
I’ve added the tests as requested and would appreciate any feedback.

P.S. The Read the Docs build is failing, but the logs indicate it’s due to an external issue unrelated to my changes.