fix: Stat call should properly handle unprefixed configurations in s3_v2 storage driver

mentioned in commit 89261ccc

mentioned in issue #1611 (closed)

mentioned in merge request gitlab-org/charts/gitlab!4319 (merged)

mentioned in merge request gitlab-org/build/CNG!2418 (merged)

mentioned in merge request omnibus-gitlab!8466 (merged)

mentioned in merge request gitlab-org/charts/gitlab!4326 (closed)