$ git clone -n https://src.fedoraproject.org/rpms/mingw-libsigc++30.git /var/lib/mock/f45-build-18572-522/root/chroot_tmpdir/scmroot/mingw-libsigc++30
Cloning into '/var/lib/mock/f45-build-18572-522/root/chroot_tmpdir/scmroot/mingw-libsigc++30'...
$ git fetch origin 228c2fe806e4e3aa19908a81113dc4e280aaf77e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/mingw-libsigc++30
 * [new ref]         228c2fe806e4e3aa19908a81113dc4e280aaf77e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 228c2fe Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild