Re-enable MYSQL in GitHub Actions testing

[peterjc]

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Reverts change made in #3837 as a work-around for #3834.

[peterjc]

Installing the libraries is working, but not the tests yet:

...
test_BWA_tool ... skipping. Install bwa and correctly set the file path to the program if you want to use it from Biopython
test_BioSQL_MySQLdb ... skipping. BioSQL test configuration file biosql.ini missing (see biosql.ini.sample)
test_BioSQL_MySQLdb_online ... skipping. internet not available
test_BioSQL_mysql_connector ... skipping. BioSQL test configuration file biosql.ini missing (see biosql.ini.sample)
test_BioSQL_mysql_connector_online ... skipping. internet not available
test_BioSQL_psycopg2 ... skipping. BioSQL test configuration file biosql.ini missing (see biosql.ini.sample)
test_BioSQL_psycopg2_online ... skipping. internet not available
test_BioSQL_sqlite3 ... ok
test_BioSQL_sqlite3_online ... skipping. internet not available
test_Blast_Record ... ok
...

[peterjc]

The CircleCI failure with pycairo has shown up on other recent pull requests, unrelated.

[peterjc]

Hmm, missing the dependencies on macOS and Windows:

...
test_BWA_tool ... skipping. Install bwa and correctly set the file path to the program if you want to use it from Biopython
test_BioSQL_MySQLdb ... skipping. Install MySQLdb or mysqlclient if you want to use mysql with BioSQL 
test_BioSQL_MySQLdb_online ... skipping. internet not available
test_BioSQL_mysql_connector ... skipping. Install mysql.connector if you want to use mysql with BioSQL 
test_BioSQL_mysql_connector_online ... skipping. internet not available
test_BioSQL_psycopg2 ... skipping. Install psycopg2 if you want to use pg with BioSQL 
test_BioSQL_psycopg2_online ... skipping. internet not available
test_BioSQL_sqlite3 ... ok
test_BioSQL_sqlite3_online ... skipping. internet not available
test_Blast_Record ... ok
...

And on Linux missing psycopg2 and it looks like the MySQL settings need adjusting:

...
test_BWA_tool ... skipping. Install bwa and correctly set the file path to the program if you want to use it from Biopython
test_BioSQL_MySQLdb ... skipping. Connection failed, check settings if you plan to use BioSQL: (1045, "Access denied for user 'root'@'localhost' (using password: NO)")
test_BioSQL_MySQLdb_online ... skipping. internet not available
test_BioSQL_mysql_connector ... skipping. Connection failed, check settings if you plan to use BioSQL: 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
test_BioSQL_mysql_connector_online ... skipping. internet not available
test_BioSQL_psycopg2 ... skipping. Install psycopg2 if you want to use pg with BioSQL 
test_BioSQL_psycopg2_online ... skipping. internet not available
test_BioSQL_sqlite3 ... ok
test_BioSQL_sqlite3_online ... skipping. internet not available
test_Blast_Record ... ok
...

[peterjc]

Worked, but looks like we're hitting a time limit now?

...
test_BWA_tool ... skipping. Install bwa and correctly set the file path to the program if you want to use it from Biopython
test_BioSQL_MySQLdb ... ok
test_BioSQL_MySQLdb_online ... skipping. internet not available
test_BioSQL_mysql_connector ... ok
test_BioSQL_mysql_connector_online ... skipping. internet not available
test_BioSQL_psycopg2 ... skipping. Install psycopg2 if you want to use pg with BioSQL 
test_BioSQL_psycopg2_online ... skipping. internet not available
test_BioSQL_sqlite3 ... ok
test_BioSQL_sqlite3_online ... skipping. internet not available
test_Blast_Record ... ok
...

[peterjc]

Rebasing, and leaving out the Windows attempt which failed.

[peterjc]

So close, timed out on Linux 3.10 (although all the Linux tests are a bit slow).

One solution might be to vary the optional modules by Python version, e.g. test graphical output under Python 3.10, test SQL bits under Python 3.11, etc.