Fix camera override button not updating in 2D scenes

Reconnect accidentally disconnected signal play_pressed to update the button
and enable camera override after launching a project in the editor.

editor/plugins/canvas_item_editor_plugin.cpp

@@ -4977,7 +4977,7 @@ CanvasItemEditor::CanvasItemEditor() {
 	SceneTreeDock::get_singleton()->connect("node_created", callable_mp(this, &CanvasItemEditor::_node_created));
 	SceneTreeDock::get_singleton()->connect("add_node_used", callable_mp(this, &CanvasItemEditor::_reset_create_position));
 
-	EditorNode::get_singleton()->call_deferred(SNAME("connect"), callable_mp(this, &CanvasItemEditor::_update_override_camera_button).bind(true));
+	EditorNode::get_singleton()->call_deferred(SNAME("connect"), "play_pressed", callable_mp(this, &CanvasItemEditor::_update_override_camera_button).bind(true));
 	EditorNode::get_singleton()->call_deferred(SNAME("connect"), "stop_pressed", callable_mp(this, &CanvasItemEditor::_update_override_camera_button).bind(false));
 
 	// A fluid container for all toolbars.