Set autovacuum parameters for acs snapshot table

[rautenrieth-da]

The acs_snapshot_data and acs_snapshot tables are almost append-only (we only had a one-time process deleting corrupt snapshots).

Other append-only tables use the following setting, guaranteeing regular autovacuum regardless of table size

ALTER TABLE update_history_exercises SET (autovacuum_analyze_scale_factor = 0, autovacuum_analyze_threshold = 20000);