Stop reading from event_edges.is_state to prepare for dropping it.

[reivilibre]

Gets one step further in the job started by matrix-org/synapse#12893

Part of: #20026

This pull request is commit-by-commit review friendly.

1. Bump SCHEMA_VERSION to 95

2. Force event_edges_drop_invalid_rows update into foreground

3. Stop reading from event_edges.is_state

Manual testing strategy

Unfortunately it's quite difficult to actually trigger this.

You need to:

• check out an old full_schema, e.g. 54 which was present when v1.62.0 was released
• remove the version 72 full_schema, as it already has the background update applied
• remove some deltas that are broken when upgrading across such a large version gap (!) It's difficult to maintain schema upgrade compatibility across large version gaps because of background updates #20070
• then run any trial test with Postgres enabled to prove that the database schema applies

git checkout v1.62.0 -- synapse/storage/schema/state/full_schemas/54                
git checkout v1.62.0 -- synapse/storage/schema/main/full_schemas/54                                                                                                
git checkout v1.62.0 -- synapse/storage/schema/common/full_schemas/54
rm -r synapse/storage/schema/*/full_schemas/72
rm synapse/storage/schema/main/delta/58/10_pushrules_enabled_delete_obsolete.sql
rm synapse/storage/schema/main/delta/79/04_mitigate_stream_ordering_update_race.py
rm synapse/storage/schema/main/delta/56/redaction_censor3_fix_update.sql.postgres
rm synapse/storage/schema/main/delta/60/01recreate_stream_ordering.sql.postgres
SYNAPSE_TEST_LOG_LEVEL=DEBUG SYNAPSE_POSTGRES=1 poetry run trial tests.handlers.test_sliding_sync.ComputeInterestedRoomsTestCase_new.test_no_joins_after_to_token

As light validation, I purposefully inserted a SQL error into the query to check that it is caught by the above testing strategy.

[github-actions]

Schema Diff

Please check that this looks as expected!

common (sqlite)

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common (postgres)

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main (sqlite)

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main (postgres)

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state (sqlite)

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state (postgres)

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