$ git clone -n https://src.fedoraproject.org/rpms/R-mvtnorm.git /var/lib/mock/f45-build-6278-347/root/chroot_tmpdir/scmroot/R-mvtnorm
Cloning into '/var/lib/mock/f45-build-6278-347/root/chroot_tmpdir/scmroot/R-mvtnorm'...
$ git fetch origin 87ca8c3f54e77dd41515ccd547cb092007decb24:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-mvtnorm
 * [new ref]         87ca8c3f54e77dd41515ccd547cb092007decb24 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 87ca8c3 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild