Merge pull request #54773 from nextcloud/backport/54744/stable30

[stable30] fix: cast fileid to string in getMountsForFileId

Author: blizzz

lib/private/Files/Config/UserMountCache.php

@@ -353,6 +353,7 @@ private function getCacheInfoFromFileId($fileId): array {
 	 * @since 9.0.0
 	 */
 	public function getMountsForFileId($fileId, $user = null) {
+		$fileId = (int) $fileId;
 		try {
 			[$storageId, $internalPath] = $this->getCacheInfoFromFileId($fileId);
 		} catch (NotFoundException $e) {