friendship tests

[samjam48]

Test the connections table to assert it is working

• [ ] - find all connections
• [ ] - find specific connection by id
• [ ] - find all connections by user_id
• [ ] - create connection will fail with incorrect information
• [ ] - create connection works with correct information
• [ ] - delete connection
• [ ] - will not create a connection that already exists

[Manimaran11]

@samjam48 I would like to look into this issue. Please let me know its fine https://github.com/syncify-team/syncify-back-end/pull/132/files