FIX: Remove HAS_WARPED Metadata when logging into a new server

[TreemanKing]

Checks if player has HAS_WARPED metadata when joining a server (shouldn't have it when logging/joining a server anyway) and removes it if they do.

Alternatively it could be put in the PlayerQuitEvent but I don't think it should be fine for the PlayerJoinEvent.

Was tested in a live environment by @RillSoji

Fixes #329