Continuation of #2444, which introduced the commit
bf7fb89178 but only added
the label and the tests.
The tooltip explaining what AGit is and its advantages is not
meant to advertise AGit - it is meant to inform the reader that
is presumably not familiar with the workflow that they will not
be able to find a fork or a branch associated with the Pull Request
as a direct consequence of this workflow.
Issue #2474 mentions that we should show instructions on how to
fetch an AGit-created Pull Request, and this is the plan. However,
this may take time, so I might as well make the label a bit more
"complete" and less out-of-place for now if we do not manage to
improve these instructions until the next release (Forgejo v1.22).
Refs: https://codeberg.org/forgejo/forgejo/issues/2474
5bc7b8baf8