Function pg_snapshot_failpoint_pause 

async fn pg_snapshot_failpoint_pause(table: &str)

Test-only pause point, run before any data of table is emitted. Configuring the failpoint as pg_snapshot_pause=return(<table name>) holds the snapshot of that table until the failpoint is deactivated. return(<table name>:<millis>) holds it for that long instead, so the snapshot completes in the same dataflow incarnation. Tables are snapshotted in OID order, so tables ordered before the paused one complete their snapshots.