$ git clone -n https://src.fedoraproject.org/rpms/rubygem-xml-simple.git /var/lib/mock/f45-build-35473-695/root/chroot_tmpdir/scmroot/rubygem-xml-simple
Cloning into '/var/lib/mock/f45-build-35473-695/root/chroot_tmpdir/scmroot/rubygem-xml-simple'...
$ git fetch origin aea1ee2389b65c6ba9967cf6afda6bb66d65f4d0:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/rubygem-xml-simple
 * [new ref]         aea1ee2389b65c6ba9967cf6afda6bb66d65f4d0 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at aea1ee2 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild