CU-8692wgmkm: Add neo4J connector that was removed from MedCAT

[mart-r]

Add (at least temporarily) the stuff removed in MedCAT PR: https://github.com/CogStack/MedCAT/pull/356

The workflow is likely to fail due to the fact that py2neo seems to have ceased to exist.

Will leave it up here until the issue gets resolved or someone rewrites it using something else.

[antsh3k]

This needs an up to date rewrite with the python neo4j package, or something similar. Do not merge till then