Get the msgid directly from the MessageIdStore (#5606)

We don't need to create message definitions to get their msgids.

The level of indirection may suggest we need to refactor a
little here. Maybe we actually need message definition only
when we want to display the messages.

Here's the current implementation of get_message_definitions:

    def get_message_definitions(self, msgid_or_symbol: str) -> List[MessageDefinition]:
        """Returns the Message definition for either a numeric or symbolic id."""
        return [
            self._messages_definitions[m]
            for m in self.message_id_store.get_active_msgids(msgid_or_symbol)
        ]

Author: Pierre-Sassoulas

pylint/lint/pylinter.py

@@ -1435,8 +1435,7 @@ def is_message_enabled(
             if confidence.name not in self.config.confidence:
                 return False
         try:
-            message_definitions = self.msgs_store.get_message_definitions(msg_descr)
-            msgids = [md.msgid for md in message_definitions]
+            msgids = self.msgs_store.message_id_store.get_active_msgids(msg_descr)
         except exceptions.UnknownMessageError:
             # The linter checks for messages that are not registered
             # due to version mismatch, just treat them as message IDs