Change from showHTML to show

There is no need to use `showHTML` here.

apps/files/js/files.js

@@ -135,7 +135,7 @@ var Files = {
 			return;
 		}
 		if (initStatus === '1') { // encryption tried to init but failed
-			OC.Notification.showHtml(t('files', 'Invalid private key for Encryption App. Please update your private key password in your personal settings to recover access to your encrypted files.'));
+			OC.Notification.show(t('files', 'Invalid private key for Encryption App. Please update your private key password in your personal settings to recover access to your encrypted files.'));
 			return;
 		}
 		if (encryptedFiles === '1') {