$ git clone -n https://src.fedoraproject.org/rpms/R-BiocGenerics.git /var/lib/mock/f45-build-5890-345/root/chroot_tmpdir/scmroot/R-BiocGenerics
Cloning into '/var/lib/mock/f45-build-5890-345/root/chroot_tmpdir/scmroot/R-BiocGenerics'...
$ git fetch origin 231a4e12fa29102d657cc3687002d43d6478000a:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-BiocGenerics
 * [new ref]         231a4e12fa29102d657cc3687002d43d6478000a -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 231a4e1 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild