Fix Preview Provider psalm

Signed-off-by: John Molakvoæ <[email protected]>

lib/private/Preview/ProviderV2.php

@@ -96,6 +96,7 @@ protected function getLocalFile(File $file, int $maxSize = null): string {
 			$this->tmpFiles[] = $absPath;
 			return $absPath;
 		} else {
+			/** @var string */
 			return $file->getStorage()->getLocalFile($file->getInternalPath());
 		}
 	}

lib/public/Files/Storage.php

@@ -330,7 +330,7 @@ public function touch($path, $mtime = null);
 	 * The local version of the file can be temporary and doesn't have to be persistent across requests
 	 *
 	 * @param string $path
-	 * @return string|bool
+	 * @return string
 	 * @since 6.0.0
 	 */
 	public function getLocalFile($path);