$ git clone -n https://src.fedoraproject.org/rpms/R-pkgconfig.git /var/lib/mock/f45-build-6300-347/root/chroot_tmpdir/scmroot/R-pkgconfig
Cloning into '/var/lib/mock/f45-build-6300-347/root/chroot_tmpdir/scmroot/R-pkgconfig'...
$ git fetch origin 1038df6393d4ea30382de8773ce45b64afbd7f92:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/R-pkgconfig
 * [new ref]         1038df6393d4ea30382de8773ce45b64afbd7f92 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 1038df6 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild