$ git clone -n https://src.fedoraproject.org/rpms/tkimg.git /var/lib/mock/f45-build-37221-712/root/chroot_tmpdir/scmroot/tkimg
Cloning into '/var/lib/mock/f45-build-37221-712/root/chroot_tmpdir/scmroot/tkimg'...
$ git fetch origin 600a5ed2b4c37a752a7edc7ac6c703431e4149f2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/tkimg
 * [new ref]         600a5ed2b4c37a752a7edc7ac6c703431e4149f2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 600a5ed update to 2.1.1, bump libtiff to 4.7.2 (the tkimg libtiff library glue still versions at 4.7.1, because I didnt want to break compat when/if upstream makes a similar change)