[dt] use 'parse_datetime_iso()' for ISO formats

gallery_dl/extractor/wikimedia.py

@@ -75,8 +75,7 @@ class WikimediaExtractor(BaseExtractor):
             for m in image["commonmetadata"] or ()}
 
         text.nameext_from_url(image["canonicaltitle"].partition(":")[2], image)
-        image["date"] = self.parse_datetime(
-            image["timestamp"], "%Y-%m-%dT%H:%M:%SZ")
+        image["date"] = self.parse_datetime_iso(image["timestamp"])
 
     def items(self):
         for info in self._pagination(self.params):