$ git clone -n https://src.fedoraproject.org/rpms/R-bindrcpp.git /var/lib/mock/f45-build-5973-345/root/chroot_tmpdir/scmroot/R-bindrcpp
Cloning into '/var/lib/mock/f45-build-5973-345/root/chroot_tmpdir/scmroot/R-bindrcpp'...
$ git fetch origin 864af434bd5dd07e0bc0b336ce9e883bde8312be:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-bindrcpp
 * [new ref]         864af434bd5dd07e0bc0b336ce9e883bde8312be -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 864af43 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild