Style: Replace header guards with #pragma once

scene/resources/image_texture.h

@@ -28,8 +28,7 @@
 /* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
 /**************************************************************************/
 
-#ifndef IMAGE_TEXTURE_H
-#define IMAGE_TEXTURE_H
+#pragma once
 
 #include "scene/resources/texture.h"
 
@@ -202,5 +201,3 @@ public:
 
 	virtual Ref<Resource> create_placeholder() const;
 };
-
-#endif // IMAGE_TEXTURE_H