Compatibility broken with newer MariaDB versions / `--innodb-snapshot-isolation=ON`

[meisterT]

MariaDB version 11.6.2 (and perhaps other versions) set --innodb-snapshot-isolation=ON which causes multiple queries in DOMjudge to fail.

#2843 is likely part of a fix, perhaps #2844 also helps

Some more references:

• https://mariadb.com/resources/blog/isolation-level-violation-testing-and-debugging-in-mariadb/
• https://jira.mariadb.org/browse/MDEV-26642?orderby=created+DESC%2C+priority+DESC%2C+updated+DESC
• https://jira.mariadb.org/browse/MDEV-35124?orderby=created+DESC%2C+priority+DESC%2C+updated+DESC
• https://jepsen.io/analyses/mysql-8.0.34

[meisterT]

Examples how this can manifest itself:

• An exception occurred while executing a query: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry \'1541319\' for key \'PRIMARY\'',
• An exception occurred while executing a query: SQLSTATE[HY000]: General error: 1020 Record has changed since last read in table 'judgetask'
• SQLSTATE[HY000]: General error: 1205 Lock wait timeout exceeded; try restarting transaction
• An exception occurred while executing a query: SQLSTATE[HY000]: General error: 1020 Record has changed since last read in table 'queuetask'