$ git clone -n https://src.fedoraproject.org/rpms/kactivitymanagerd.git /var/lib/mock/f40-build-2489876-61655/root/chroot_tmpdir/scmroot/kactivitymanagerd
Cloning into '/var/lib/mock/f40-build-2489876-61655/root/chroot_tmpdir/scmroot/kactivitymanagerd'...
$ git fetch origin aefce6e6ac1aaaf3c93d6e3f1b7ea792e6066e41:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kactivitymanagerd
 * [new ref]         aefce6e6ac1aaaf3c93d6e3f1b7ea792e6066e41 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at aefce6e 6.0.0