add "lib" lookup and/or skip to test_pickle_rows_other_procses

[zzzeek]

Discussed in https://github.com/sqlalchemy/sqlalchemy/discussions/11266

this test assumes "lib" is in the PYTHONPATH which is wrong:

https://github.com/sqlalchemy/sqlalchemy/blob/483edf651f6c3db6729f8d75265241b67ccd6b80/test/sql/test_resultset.py#L521-L539

[sqla-tester]

Federico Caselli has proposed a fix for this issue in the main branch:

Fix missing pythonpath in test that use subprocess https://gerrit.sqlalchemy.org/c/sqlalchemy/sqlalchemy/+/5251

[sqla-tester]

Federico Caselli has proposed a fix for this issue in the rel_2_0 branch:

Fix missing pythonpath in test that use subprocess https://gerrit.sqlalchemy.org/c/sqlalchemy/sqlalchemy/+/5252