Apply php-cs-fixer changes

lib/Service/OcrService.php

@@ -232,7 +232,7 @@ private function processTagsAfterSuccessfulOcr(File $file, WorkflowSettings $set
 	 * @param int $fileId The id of the file to write. Used for locking.
 	 * @param int $fileMtime The mtime of the new file. Can be used to restore the original modification time of the non-OCR file.
 	 */
-	private function createNewFileVersion(string $filePath, string $ocrContent, int $fileId, int $fileMtime = null) : void {
+	private function createNewFileVersion(string $filePath, string $ocrContent, int $fileId, ?int $fileMtime = null) : void {
 		$dirPath = dirname($filePath);
 		$filename = basename($filePath);