$ git clone -n https://src.fedoraproject.org/rpms/jaxb-api2.git /var/lib/mock/f38-build-side-42-init-devel-574844-25998/root/chroot_tmpdir/scmroot/jaxb-api2
Cloning into '/var/lib/mock/f38-build-side-42-init-devel-574844-25998/root/chroot_tmpdir/scmroot/jaxb-api2'...
$ git fetch origin d81bc6d7cee82f41128bc5865fbf911c556e06e6:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/jaxb-api2
 * [new ref]         d81bc6d7cee82f41128bc5865fbf911c556e06e6 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d81bc6d Add javapackages tests