Ship joining starts on locked (#3346)

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## About The Pull Request
Ship's start on locked instead of open
Idea from #772
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## Why It's Good For The Game
No longer can an assistant join your ship faster then you can, rejoice
in time to write your memo and change your ships name.
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## Changelog

:cl:
fix: ships now start closed. shiptesters be writing there memos and ship
names.
/:cl:

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code/modules/overmap/ships/controlled_ship_datum.dm

@@ -56,7 +56,7 @@
 	var/owner_check_timer_id
 
 	/// The ship's join mode. Controls whether players can join freely, have to apply, or can't join at all.
-	var/join_mode = SHIP_JOIN_MODE_OPEN
+	var/join_mode = SHIP_JOIN_MODE_CLOSED
 	/// Lazylist of /datum/ship_applications for this ship. Only used if join_mode == SHIP_JOIN_MODE_APPLY
 	var/list/datum/ship_application/applications