[NO GBP] Fixes camera consoles crashing clients (#90523)

## About The Pull Request
Fixes client crashes when closing windows with byond rendered content.
The issue was reintroduced by
https://github.com/tgstation/tgstation/pull/90460
Closes: https://github.com/tgstation/tgstation/issues/89330
It does work. (sometimes?)
I didn't manage to reproduce the issue locally, but it exists live. 
## Why It's Good For The Game
Less bugs
## Changelog
🆑

fix: camera consoles, admin supply pod launcher etc. no longer close
game when they are closed
/🆑

code/_onclick/hud/rendering/plane_master_group.dm

@@ -15,7 +15,7 @@
 	var/map = ""
 	/// Controls the screen_loc that owned plane masters will use when generating relays. Due to a Byond bug, relays using the CENTER positional loc
 	/// Will be improperly offset
-	var/relay_loc = "SCREEN_SOUTHWEST"
+	var/relay_loc = "1,1"
 
 /datum/plane_master_group/New(key, map = "")
 	. = ..()

code/_onclick/hud/rendering/render_plate.dm

@@ -393,7 +393,7 @@
  * Other vars such as alpha will automatically be applied with the render source
  */
 /atom/movable/screen/plane_master/proc/generate_render_relays()
-	var/relay_loc = home?.relay_loc || "SCREEN_SOUTHWEST"
+	var/relay_loc = home?.relay_loc || "1,1"
 	// If we're using a submap (say for a popup window) make sure we draw onto it
 	if(home?.map)
 		relay_loc = "[home.map]:[relay_loc]"
@@ -427,7 +427,7 @@
 	if(!length(relays) && !initial(render_target))
 		render_target = OFFSET_RENDER_TARGET(get_plane_master_render_base(name), offset)
 	if(!relay_loc)
-		relay_loc = "SCREEN_SOUTHWEST"
+		relay_loc = "1,1"
 		// If we're using a submap (say for a popup window) make sure we draw onto it
 		if(home?.map)
 			relay_loc = "[home.map]:[relay_loc]"