$ git clone -n https://src.fedoraproject.org/rpms/rpm-ostree.git /var/lib/mock/f31-build-86053-31648/root/chroot_tmpdir/scmroot/rpm-ostree
Cloning into '/var/lib/mock/f31-build-86053-31648/root/chroot_tmpdir/scmroot/rpm-ostree'...
$ git reset --hard dd2c49070002cc775d1336fef11acfb528ec9478
HEAD is now at dd2c490 Release 2019.5