$ git clone -n https://src.fedoraproject.org/rpms/gtksourceviewmm3.git /var/lib/mock/f45-build-13189-447/root/chroot_tmpdir/scmroot/gtksourceviewmm3
Cloning into '/var/lib/mock/f45-build-13189-447/root/chroot_tmpdir/scmroot/gtksourceviewmm3'...
$ git fetch origin 32b0c310b3f6512ec91d0f0bdb224d3ec41b2d19:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/gtksourceviewmm3
 * [new ref]         32b0c310b3f6512ec91d0f0bdb224d3ec41b2d19 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 32b0c31 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild