$ git clone -n https://src.fedoraproject.org/rpms/ghc-blaze-builder.git /var/lib/mock/f45-build-10026-412/root/chroot_tmpdir/scmroot/ghc-blaze-builder
Cloning into '/var/lib/mock/f45-build-10026-412/root/chroot_tmpdir/scmroot/ghc-blaze-builder'...
$ git fetch origin 135b7e9a790c5ce55089259b21e3356734530d2e:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/ghc-blaze-builder
 * [new ref]         135b7e9a790c5ce55089259b21e3356734530d2e -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at 135b7e9 Rebuilt for https://fedoraproject.org/wiki/Fedora_45_Mass_Rebuild