Usage ping updates

What does this MR do?

1. Allow disabling usage ping in gitlab.yml.
2. Send the hostname of the instance in the usage ping.

Version app MR: https://dev.gitlab.org/gitlab/version-gitlab-com/merge_requests/63

Screenshots (if relevant)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests
  • Added for this feature/bug
  • All builds are passing
• Conform by the merge request performance guides
• Conform by the style guides
• Branch has no merge conflicts with master (if it does - rebase it please)
• Squashed related commits together

What are the relevant issue numbers?

Closes https://gitlab.com/gitlab-org/gitlab-ce/issues/31741 and https://gitlab.com/gitlab-org/gitlab-ce/issues/31453.