$ git clone -n https://src.fedoraproject.org/rpms/copr-backend.git /var/lib/mock/f39-build-2144740-50869/root/chroot_tmpdir/scmroot/copr-backend
Cloning into '/var/lib/mock/f39-build-2144740-50869/root/chroot_tmpdir/scmroot/copr-backend'...
$ git fetch origin 2e7a59b542ba896c8d0bd058049c56086b7a33b5:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/copr-backend
 * [new ref]         2e7a59b542ba896c8d0bd058049c56086b7a33b5 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2e7a59b Update copr-backend to 1.173-1