fix: Reduced log to warning if multiple navigation polygons are enabled while in editor

fixes godot-escoria/escoria-issues#103

addons/escoria-core/game/core-scripts/esc_terrain.gd

@@ -63,7 +63,7 @@ func _ready():
 	for n in get_children():
 		if n is NavigationPolygonInstance:
 			if n.enabled:
-				if navigation_enabled_found:
+				if !Engine.is_editor_hint() and navigation_enabled_found:
 					escoria.logger.report_errors(
 						"ESCTerrain:_ready()",
 						[
@@ -71,6 +71,14 @@ func _ready():
 							"at the same time."
 						]
 					)
+				elif Engine.is_editor_hint():
+					escoria.logger.report_warnings(
+						"ESCTerrain:_ready()",
+						[
+							"Multiple NavigationPolygonInstances enabled " + \
+							"at the same time."
+						]
+					)
 				navigation_enabled_found = true
 				current_active_navigation_instance = n