Backporting #96 to 1.5.1

See #96
Revert "PHPCS: use  Squiz sniff for strict equality checks"

This reverts commit 88efb579ac151033398812a2739d15b7ea614871.
Do not attempt to ALTER tables in the update tests

Doing this causes the database transaction to be committed.

We still alter tables in the 1.5.1 update test, but we `ROLLBACK` all
changes, so the database stays clean.

See #97
Call parent::tearDown() in the points test case

Otherwise, all of the `_drop_temporary_tables()` methods don’t get
removed, causing the 1.5.1 update tests not to work. It causes other
mischief as well, including not reporting the use of deprecated stuff,
like we were actually using in the comment and post points hook and
1.2.0 update tests.

See #97