Ignore intersphinx std:doc objects from DocItem generation (#3446)

These items caused issues that led to spam in the #dev-log channel about stale inventories (though inventories were not stale).

All std:doc items are accompanied by a module item or a label item that contains actual contents that are compatible with our doc command, so hopefully ignoring these items will not cause any reduced functionality of the command.

When testing locally this removes all symbols with empty symbol IDs and stops the warning spam to #dev-log.

Author: jb3

bot/exts/info/doc/_cog.py

@@ -26,6 +26,11 @@
 
 log = get_logger(__name__)
 
+# groups to ignore from parsing
+IGNORE_GROUPS = (
+    "std:doc",
+)
+
 # symbols with a group contained here will get the group prefixed on duplicates
 FORCE_PREFIX_GROUPS = (
     "term",
@@ -80,6 +85,8 @@ def update_single(self, package_name: str, base_url: str, inventory: InventoryDi
 
         for group, items in inventory.items():
             for symbol_name, relative_doc_url in items:
+                if group in IGNORE_GROUPS:
+                    continue
 
                 # e.g. get 'class' from 'py:class'
                 group_name = group.split(":")[1]