* refactor user graphql
- remove isLoggedIn query
- currentUser query only for authenticated, currenUser always returns a
User
- currentUser query implementation uses neo4jgraphql with id parameter
- remove custom email field from user
- fix bug in frontend when there is no categories
* remove comment
* remove unused filter
* fix currentuser test
* fixedswitchUserRole mutation
* fix categories
* After creating the post, the author of it automatically observes it to get notifications when there are interactions
* a user that comments a post, automatically observes that post to get notifications when there are more interactions on that post
* mutation that switches the state of the observation of a post on and off