$ git clone -n https://src.fedoraproject.org/rpms/tinycompress.git /var/lib/mock/f40-build-792539-138444/root/chroot_tmpdir/scmroot/tinycompress
Cloning into '/var/lib/mock/f40-build-792539-138444/root/chroot_tmpdir/scmroot/tinycompress'...
$ git fetch origin 2efc05e9e63697422983202d0cc5d2550d11a588:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/tinycompress
 * [new ref]         2efc05e9e63697422983202d0cc5d2550d11a588 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 2efc05e update to 1.2.11