Fix: redirect non-SSL request for gitlab registry to valid URL

What does this MR do?

Fixes a bug in nginx ssl configuration for gitlab runner. Redirect URLs contained a colon between host and path.

Are there points in the code the reviewer needs to double check?

Unifies the configuration with gitlab-ssl (https://gitlab.com/gitlab-org/gitlab-ce/blob/23f705f2d0f10ed765929afa923ee096d9f0e136/lib/support/nginx/gitlab-ssl#L79) and gitlab-pages-ssl (https://gitlab.com/gitlab-org/gitlab-ce/blob/23f705f2d0f10ed765929afa923ee096d9f0e136/lib/support/nginx/gitlab-pages-ssl#L17).

Why was this MR needed?

The invalid redirect URLs cause an error for Let's encrypt cert request validation. Therefore using webroot plugin of certbot is not possible.

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• API support added
• Tests added for this feature/bug
• Conforms to the code review guidelines
  • Has been reviewed by a UX Designer
  • Has been reviewed by a Frontend maintainer
  • Has been reviewed by a Backend maintainer
  • Has been reviewed by a Database specialist
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides
• If you have multiple commits, please combine them into a few logically organized commits by squashing them
• Internationalization required/considered
• End-to-end tests pass (package-and-qa manual pipeline job)

What are the relevant issue numbers?

#43664 (moved)