Change meta_knowledge_graph to be the most specific categories and properties

[gaurav]

At the moment, I believe (possibly incorrectly) that CAM-KP's meta_knowledge_graph returns all categories and properties, but the specification says that we should return the most specific categories and predicates. This issue covers testing whether that is the case and, if so, to fix it.

[gaurav]

This will require modifying:

• https://github.com/ExposuresProvider/cam-kp-api/blob/master/src/main/resources/mkg-nodes.csv (which I believe was last generated by https://github.com/jdr0887/cam-pipeline-rust/blob/85b77451f420939ac9f0aeab5b3c812503a70277/src/bin/construct_mkg_node_map.rs)
• https://github.com/ExposuresProvider/cam-kp-api/blob/master/src/main/resources/predicates.csv (which I think is generated by https://github.com/ExposuresProvider/cam-pipeline/blob/b2ad9f8db6fe7af811b5fa4476d39cee8428af60/Makefile#L166-L171)