Update Neo4j extension to use Spring Data Neo4j.

[meistermeier]

This is a rather large PR because it will remove the Neo4j-OGM dependency and replace it with the Spring Data Neo4j.

Some background information to clarify the situation: The official Spring Data Neo4j was rewritten a few years ago to not depend on Neo4j-OGM anymore (in Spring Boot version since 2.4). This current (old) implementation is based on the fact that the Spring Boot starter still brings Neo4j-OGM as a dependency and makes use of the configured SessionFactory instance, that does not exist anymore.

Pros: No need to specify the query parts anymore but only one query/statement based on the Neo4j Cypher-DSL (https://github.com/neo4j-contrib/cypher-dsl) for readers Cons: The writer needs now, instead of the single SessionFactory,

• the Neo4jMappingContext to have knowledge about the entities
• the Neo4jTemplate for loading and mapping entities
• the (Neo4j)Driver for the simple delete operations.

While changing the mapping layer component, I decided also to upgrade all other dependencies to latest.