Update Dockerfile to install libpq5 alongside other PostgreSQL packages

Author: m3hm3t

circleci/images/extbuilder/Dockerfile

@@ -60,7 +60,7 @@ apt-get update
 pgdg_version=$(apt list -a postgresql-server-dev-${PG_MAJOR} 2>/dev/null | grep "${PG_VERSION}" | awk '{print $2}' | head -n1 )
 
 apt-get install -y --no-install-recommends --allow-downgrades \
-    libpq5=${pgdg_version}
+    libpq5=${pgdg_version} \
     libpq-dev=${pgdg_version} \
     postgresql-${PG_MAJOR}=${pgdg_version} \
     postgresql-client-${PG_MAJOR}=${pgdg_version} \