- Change double quotes to single quotes.
- Why is `OmniAuth.config.full_host` being reassigned in the integration test?
- Use `map` over `map!` to avoid `dup` in the `gitlab:info` rake task
- Other minor changes

- The test for `rake gitlab:env:info` executed the rake task, which mutated the
  list of omniauth providers, breaking subsequent tests relying on this list.

- I've changed the rake task to duplicate the providers list before modifying it.

This adds an ID-less table containing one row per file, per merge request
diff. It has a column for each attribute on Gitlab::Git::Diff that is serialised
currently, with the advantage that we can easily query the attributes of this
new table.

It does not migrate existing data, so we have fallback code when the legacy
st_diffs column is present instead. For a merge request diff to be valid, it
should have at most one of:

* Rows in this new table, with the correct merge_request_diff_id.
* A non-NULL st_diffs column.

It may have neither, if the diff is empty.

This revealed an error in our configuration generation in
gitlab:gitaly:install rake task. The fix is included

Add a Rake task to aid in rotating otp_key_base

Closes #29690

See merge request !11881

backports changed import logic from pull mirroring feature into CE

See merge request !11850