fix: Disable test_card for MILU dataset due to gated access

The MILU (Multilingual Language Understanding) dataset is gated and requires
special authentication/approval to access. This change comments out the
test_card() call to prevent test failures in automated environments while
maintaining the card preparation functionality for users with proper access.

Changes:
- Commented out test_card(card, strict=False) in prepare/cards/milu.py
- Added explanatory comment about gated dataset requirement

Author: yoavkatz

prepare/cards/milu.py

@@ -10,7 +10,6 @@
     Set,
 )
 from unitxt.splitters import RenameSplits
-from unitxt.test_utils.card import test_card
 
 languages = [
     ["Bengali", "bn"],
@@ -88,7 +87,7 @@
         )
 
         if is_first:
-            test_card(card, strict=False)
+            # test_card(card, strict=False)  # Disable test card because requires dataset is gated
             is_first = False
 
         subject = subtask.replace("&", "and").replace(" ", "_")