Bug 1678619: Release UDateFormat instance by udat_close after using it. r=zbraniecki

Depends on D100461

Differential Revision: https://phabricator.services.mozilla.com/D102256

intl/locale/DateTimeFormat.cpp

@@ -120,6 +120,8 @@ nsresult DateTimeFormat::FormatDateTime(
     }
   }
 
+  udat_close(dateTimeFormat);
+
   if (U_FAILURE(status)) {
     return NS_ERROR_FAILURE;
   }