Fix NavigationServer.set_debug_enabled() doing nothing

Fixes NavigationServer.set_debug_enabled() doing nothing because it was not updated for newer dirty flags.

(cherry picked from commit 282d772f1bedebbeacab30da7fb87302d1599104)

servers/navigation_server_3d.cpp

@@ -263,7 +263,11 @@ void NavigationServer3D::set_debug_enabled(bool p_enabled) {
 	debug_enabled = p_enabled;
 
 	if (debug_dirty) {
+		navigation_debug_dirty = true;
 		call_deferred("_emit_navigation_debug_changed_signal");
+
+		avoidance_debug_dirty = true;
+		call_deferred("_emit_avoidance_debug_changed_signal");
 	}
 #endif // DEBUG_ENABLED
 }