Always sync 1 record per stream when using `--test` or `--test=all`

Background:

• We initially tried to sync zero records per stream during --test
• We had to sync at least one record to get child results to we bumped this to 1 record if the stream was a parent.
• Now that we have --test=schema (Add `--test=schema` option to emit tap SCHEMA m... (!218 - merged)) which just sends schema definitions (and no record messages), we might as well just standardize on syncing one record per stream when --test or --test=all` is set as a CLI flag.