Joining camp requests override each other

[NitayRabi]

Overview of the problem

A new camp member can join a camp in one of two ways -

1. Sends a request to join and a camp admin approves.
2. Admin sends a request to the member and the member approves.

Steps to Reproduce

1. Send a request as a camp member to camp X.
2. Send a request as camp X's admin to the the member.
3. One or both of the requests will be deleted.

Expected behavior

**Waiting for further instructions

Actual behavior

Requests seem to be deleted.

[NitayRabi]

Fixed via #999