$ git clone -n https://src.fedoraproject.org/rpms/dtk6gui.git /var/lib/mock/f42-build-side-1-3502134-45977/root/chroot_tmpdir/scmroot/dtk6gui
Cloning into '/var/lib/mock/f42-build-side-1-3502134-45977/root/chroot_tmpdir/scmroot/dtk6gui'...
$ git fetch origin 26eed0328ba8c89d2687d0ff9baefba3cd3919e1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/dtk6gui
 * [new ref]         26eed0328ba8c89d2687d0ff9baefba3cd3919e1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 26eed03 Rebuild (qt6)