Added quotes to GITLAB_SKIP_PG_UPGRADE
Issue: Docker throws a "unary operator expected error" during build.
Fix: GITLAB_SKIP_PG_UPGRADE needs quotes because if it's not set then bash tries to execute the following:
if [ != true ]; then
Issue: Docker throws a "unary operator expected error" during build.
Fix: GITLAB_SKIP_PG_UPGRADE needs quotes because if it's not set then bash tries to execute the following:
if [ != true ]; then