Fix broken new lines in plain text mail template

core/templates/altmail.php

@@ -2,7 +2,7 @@
 print_unescaped($l->t("Hey there,\n\njust letting you know that %s shared %s with you.\nView it: %s\n\n", array($_['user_displayname'], $_['filename'], $_['link'])));
 if ( isset($_['expiration']) ) {
 	print_unescaped($l->t("The share will expire on %s.", array($_['expiration'])));
-	print_unescaped('\n\n');
+	print_unescaped("\n\n");
 }
 // TRANSLATORS term at the end of a mail
 p($l->t("Cheers!"));