Style: Replace header guards with #pragma once

modules/openxr/editor/openxr_select_runtime.h

@@ -28,8 +28,7 @@
 /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
 /**************************************************************************/
 
-#ifndef OPENXR_SELECT_RUNTIME_H
-#define OPENXR_SELECT_RUNTIME_H
+#pragma once
 
 #include "scene/gui/option_button.h"
 
@@ -46,5 +45,3 @@ private:
 	void _update_items();
 	void _on_item_selected(int p_which);
 };
-
-#endif // OPENXR_SELECT_RUNTIME_H