$ git clone -n https://src.fedoraproject.org/rpms/magic.git /var/lib/mock/f40-build-805744-144864/root/chroot_tmpdir/scmroot/magic
Cloning into '/var/lib/mock/f40-build-805744-144864/root/chroot_tmpdir/scmroot/magic'...
$ git fetch origin 5da65dc54575b40fe4a64a1687eb605bb686e35b:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/magic
 * [new ref]         5da65dc54575b40fe4a64a1687eb605bb686e35b -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5da65dc 8.3.465