Style: Replace header guards with #pragma once

platform/windows/tts_windows.h

@@ -28,8 +28,7 @@
 /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
 /**************************************************************************/
 
-#ifndef TTS_WINDOWS_H
-#define TTS_WINDOWS_H
+#pragma once
 
 #include "core/string/ustring.h"
 #include "core/templates/hash_map.h"
@@ -78,5 +77,3 @@ public:
 	TTS_Windows();
 	~TTS_Windows();
 };
-
-#endif // TTS_WINDOWS_H