$ git clone -n https://src.fedoraproject.org/rpms/R-xml2.git /var/lib/mock/f40-build-789257-135690/root/chroot_tmpdir/scmroot/R-xml2
Cloning into '/var/lib/mock/f40-build-789257-135690/root/chroot_tmpdir/scmroot/R-xml2'...
$ git fetch origin 54c34cc9edf6aaf9c17757687ef11b3557be12d4:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-xml2
 * [new ref]         54c34cc9edf6aaf9c17757687ef11b3557be12d4 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 54c34cc Rebuilt for https://fedoraproject.org/wiki/Fedora_40_Mass_Rebuild