[1.16.5] Players' TP requests can be saved, causing the JSON parser to crash the server

[vabold]

If the following is found within a pdat file for someone's UUID:

  "tpRequest": {
    "requester": "request_uuid",
    "target": "target_uuid",
    "tpHere": false // can be either
  },

The JSON method cannot instantiate the ITpRequest in the PlayerData. This causes the server to disconnect the player with an internal server error, which then causes the same error on player leave, which crashes the server.

A band-aid solution for server maintainers is to simply remove these lines from the player's UUID whenever this happens. (This can be automated as a step before server launch, so crashes only happen once.)