Update rules to SR2020.3

This updates the rules to a local build of rules repo
https://github.com/srobo/rules/ at revision
0e44ea14551c96b03f13561ed8d132110c81be3f. There are no changes
to the actual rules here, this update aims exclusively to fix
the diagram rendering issues which have been reported upstream as
RealOrangeOne/docker-pandoc#5.

Author: PeterJCLaw