Pull request #801 breaks the initialization logic of docker-entrypoint script if the postgres runs as a sidecar container to the main one in a CI environment and has PGHOST variable defined.

psql command tries to connect to postgres daemon and respects the well-known PGxxx variables during the try.

if PGHOST equals to 127.0.0.1 (or localhost), the client fails with connection refused error breaking the entrypoint script:

2021-01-18 16:44:23.932 UTC [489] LOG:  database system was shut down at 2021-01-18 16:44:21 UTC
2021-01-18 16:44:23.936 UTC [488] LOG:  database system is ready to accept connections
 done
server started

psql: could not connect to server: Connection refused
	Is the server running on host "127.0.0.1" and accepting
	TCP/IP connections on port 5432?```