Memgraph memory limit

[vincentraymond-ua]

Updates the memgraph service to remove entrypoint and set memory limit to 3000 for the following files:

• end-to-end-rest/docker-compose.yml
• morae-demo/docker-compose.memgraph.yml
• morae-demo/docker-compose.skema-rs.yml
• morae-demo/docker-compose.yml