$ git clone -n https://src.fedoraproject.org/rpms/hydrogen.git /var/lib/mock/f31-build-99308-33144/root/chroot_tmpdir/scmroot/hydrogen
Cloning into '/var/lib/mock/f31-build-99308-33144/root/chroot_tmpdir/scmroot/hydrogen'...
$ git reset --hard c7e471eddcfc74a2054647ddf7a4c5af44bf475b
HEAD is now at c7e471e - Rebuilt for https://fedoraproject.org/wiki/Fedora_31_Mass_Rebuild