implement newer database access method

[freephile]

wfGetDB() was deprecated as of REL1_39
and is being removed in REL1_44

This PR is made in reference to: #253

This PR addresses or contains:

• modify AppFactory->getConnection to be version aware
• use MediaWikiServices::getInstance()->getConnectionProvider()->getReplicaDatabase() in 1.42+
• when creating a db handle in src/PropertyAnnotators/ApprovedDatePropertyAnnotator.php, use $this->appFactory->getConnection() instead of wfGetDB()
• maybe throwing a db connection exception in annotator class methods is a code smell and getConnection should handle it?

This PR includes:

• Tests (unit/integration)
• CI build passed

Fixes #253