$ git clone -n https://src.fedoraproject.org/rpms/golang-github-opentracing-contrib-grpc.git /var/lib/mock/f41-build-1036219-18712/root/chroot_tmpdir/scmroot/golang-github-opentracing-contrib-grpc
Cloning into '/var/lib/mock/f41-build-1036219-18712/root/chroot_tmpdir/scmroot/golang-github-opentracing-contrib-grpc'...
$ git fetch origin d954381780426aaa1ac723b509f37ae74f236566:KOJI_FETCH_HEAD
From https://src.fedoraproject.org/rpms/golang-github-opentracing-contrib-grpc
 * [new ref]         d954381780426aaa1ac723b509f37ae74f236566 -> KOJI_FETCH_HEAD
$ git reset --hard KOJI_FETCH_HEAD
HEAD is now at d954381 Fix FTBFS