$ git clone -n https://src.fedoraproject.org/rpms/mumble.git /var/lib/mock/f38-build-714416-94810/root/chroot_tmpdir/scmroot/mumble
Cloning into '/var/lib/mock/f38-build-714416-94810/root/chroot_tmpdir/scmroot/mumble'...
$ git fetch origin fe02b753e4c632b21fc99395c546b04087026816:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mumble
 * [new ref]         fe02b753e4c632b21fc99395c546b04087026816 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at fe02b75 Rebuild for poco 1.12.4, resolves rhbz#2163844