💡 [Feature] Add postgres username values to default security checks

[mishaschwartz]

Description

Originally from: #428 (comment)

birdhouse-deploy/birdhouse/components/stac/default.env

Lines 1 to 4 in eaa09c2

	export STAC_POSTGRES_USER=${POSTGRES_PAVICS_USERNAME}
	export STAC_POSTGRES_PASSWORD=${POSTGRES_PAVICS_PASSWORD}
	export STAC_PGUSER=${POSTGRES_PAVICS_USERNAME}
	export STAC_PGPASSWORD=${POSTGRES_PAVICS_PASSWORD}

those should be added to the flagged security defaults as done for other user/pwd

Also if #428 is pulled in, add these to the deprecated default checks as described in #428 (comment) and #428 (comment)

References

Concerned Organizations