$ git clone -n https://src.fedoraproject.org/rpms/firejail.git /var/lib/mock/f31-build-67063-29978/root/thebuilddir/tmp/scmroot/firejail
Cloning into '/var/lib/mock/f31-build-67063-29978/root/thebuilddir/tmp/scmroot/firejail'...
$ git reset --hard b54ff3ad986e421f99dd05966709b38823be8372
HEAD is now at b54ff3a Resolved f31 build error