Add OAT hook calls for more subcommands of ALTER TABLE

Add OAT hook calls for more subcommands of ALTER TABLE

The OAT hooks are added in ALTER TABLE for the following subcommands:
- { ENABLE | DISABLE | [NO] FORCE } ROW LEVEL SECURITY
- { ENABLE | DISABLE } TRIGGER
- { ENABLE | DISABLE } RULE.  Note that there was hook for pg_rewrite,
but not for relation ALTER'ed in pg_class.

Tests are added to test_oat_hook for all the subcommand patterns gaining
hooks here.  Based on an ask from Legs Mansion.

Discussion: https://postgr.es/m/[email protected]