[RELEASE] Add TYPO3 v12 support

What's Changed

• Prevent null error when $row['subgroup'] does not exist by @imminger in #10
• [FEATURE] Add TYPO3 v12 support and drop v10 support by @bmack in #11

New Contributors

• @imminger made their first contribution in #10
• @bmack made their first contribution in #11

Full Changelog: 2.1.0...2.2.0