Apply T243985 to wmf wikis

1. ALTERs to run: https://gerrit.wikimedia.org/r/c/mediawiki/extensions/Translate/+/817892/5/sql/mysql/patch-revtag-unique-to-pk.sql
2. Where to run those changes: s3 (wikis T314140#8115150), s4, s7 (frwiktionary and metawiki), s8
3. When to run those changes: any time
4. If the schema change is backwards compatible: Yes
5. If the schema change has been tested already on some of the test/beta wikis: beta already running with the new schema
6. if the data should be made available on the labs replicas and/or dumps: no change of the existing rules

Due to a bug in the schema change generator (T314138) the DROP + ALTER should be rewritten to be atomic

alter table revtag drop key rt_type_page_revision, ADD  PRIMARY KEY (rt_type, rt_page, rt_revision);

Progress

• s3 (T314140#8115150)
• s4
• s7 (frwiktionary and metawiki)
• s8