Fix Deterred Crashsite Offset (#3717)

# About the pull request

This PR fixes an oversight where a deterred crashsite does not get
positioned the same as a non-deterred one.

# Explain why it's good for the game

Fixes #3593 or atleast should much better mitigate it making it so a
deterred crashsite positions the same as a non-deterred.

# Testing Photographs and Procedure
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<summary>Screenshots & Videos</summary>

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# Changelog
:cl: Drathek
fix: Fixed the crashsite offset for a hijack shuttle that gets deterred
by the MGAD System
/:cl:

code/modules/shuttle/dropship_hijack.dm

@@ -1,3 +1,5 @@
+#define HIJACK_CRASH_SITE_OFFSET_X -5
+#define HIJACK_CRASH_SITE_OFFSET_Y -11
 
 /datum/dropship_hijack
 	var/obj/docking_port/mobile/shuttle
@@ -90,9 +92,10 @@
 
 	var/obj/docking_port/stationary/marine_dropship/crash_site/target_site = new()
 	crash_site = target_site
-	crash_site.x = target.x - 5
-	crash_site.y = target.y - 11
-	crash_site.z = target.z
+	var/turf/offset_target = locate(target.x + HIJACK_CRASH_SITE_OFFSET_X, target.y + HIJACK_CRASH_SITE_OFFSET_Y, target.z)
+	if(!offset_target)
+		offset_target = target // Welp the offsetting failed so...
+	target_site.forceMove(offset_target)
 
 	target_site.name = "[shuttle] crash site"
 	target_site.id = "crash_site_[shuttle.id]"
@@ -116,7 +119,10 @@
 		remaining_crash_sites -= target_ship_section
 		var/new_target_ship_section = pick(remaining_crash_sites)
 		var/turf/target = get_crashsite_turf(new_target_ship_section)
-		crash_site.Move(target)
+		var/turf/offset_target = locate(target.x + HIJACK_CRASH_SITE_OFFSET_X, target.y + HIJACK_CRASH_SITE_OFFSET_Y, target.z)
+		if(!offset_target)
+			offset_target = target // Welp the offsetting failed so...
+		crash_site.forceMove(offset_target)
 		marine_announcement("A hostile aircraft on course for the [target_ship_section] has been successfully deterred.", "IX-50 MGAD System")
 		target_ship_section = new_target_ship_section
 		// TODO mobs not alerted
@@ -218,3 +224,6 @@
 		else
 			CRASH("Crash site [ship_section] unknown.")
 	return pick(turfs)
+
+#undef HIJACK_CRASH_SITE_OFFSET_X
+#undef HIJACK_CRASH_SITE_OFFSET_Y