$ git clone -n https://src.fedoraproject.org/rpms/calibre.git /var/lib/mock/f39-build-1661277-40659/root/chroot_tmpdir/scmroot/calibre
Cloning into '/var/lib/mock/f39-build-1661277-40659/root/chroot_tmpdir/scmroot/calibre'...
$ git fetch origin 42689225357a7e44774e88793011ada74ad105ee:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/calibre
 * [new ref]         42689225357a7e44774e88793011ada74ad105ee -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 4268922 Rebuild (qt6)