Add test to instatiate all base models

tests/policies/test_pi0_openpi.py

@@ -51,7 +51,7 @@ def test_policy_instantiation():
         print(f"✓ Forward pass successful. Loss: {loss_dict['loss']:.4f}")
     except Exception as e:
         print(f"✗ Forward pass failed: {e}")
-        return False
+        raise
 
     print("\nTesting action prediction...")
     try:
@@ -60,9 +60,7 @@ def test_policy_instantiation():
         print(f"✓ Action prediction successful. Action shape: {action.shape}")
     except Exception as e:
         print(f"✗ Action prediction failed: {e}")
-        return False
-
-    return True
+        raise
 
 
 @require_nightly_gpu
@@ -80,7 +78,6 @@ def test_config_creation():
         print(f"  Config type: {type(config).__name__}")
         print(f"  PaliGemma variant: {config.paligemma_variant}")
         print(f"  Action expert variant: {config.action_expert_variant}")
-        return True
     except Exception as e:
         print(f"✗ Config creation failed: {e}")
-        return False
+        raise