$ git clone -n https://src.fedoraproject.org/rpms/bluejay.git /var/lib/mock/f42-build-side-1-3562218-46722/root/chroot_tmpdir/scmroot/bluejay
Cloning into '/var/lib/mock/f42-build-side-1-3562218-46722/root/chroot_tmpdir/scmroot/bluejay'...
$ git fetch origin 5fe8028440561eca1f25f516d493e1b5c286199f:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/bluejay
 * [new ref]         5fe8028440561eca1f25f516d493e1b5c286199f -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 5fe8028 Update to version 1.0.3 (rhbz#2369903)