$ git clone -n https://src.fedoraproject.org/rpms/yaml-cpp.git /var/lib/mock/f45-build-39198-732/root/chroot_tmpdir/scmroot/yaml-cpp
Cloning into '/var/lib/mock/f45-build-39198-732/root/chroot_tmpdir/scmroot/yaml-cpp'...
$ git fetch origin db6c2dc0cd537bc9b9fe00f5b4f80f550d8560d1:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/yaml-cpp
 * [new ref]         db6c2dc0cd537bc9b9fe00f5b4f80f550d8560d1 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at db6c2dc Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild