$ git clone -n https://src.fedoraproject.org/rpms/kdecoration.git /var/lib/mock/f42-build-side-1-3533520-46362/root/chroot_tmpdir/scmroot/kdecoration
Cloning into '/var/lib/mock/f42-build-side-1-3533520-46362/root/chroot_tmpdir/scmroot/kdecoration'...
$ git fetch origin 26dfe8adda3e42bac3eae9b88ed18d97aadc8ff2:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/kdecoration
 * [new ref]         26dfe8adda3e42bac3eae9b88ed18d97aadc8ff2 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 26dfe8a 6.3.5