chore: Handle ImportError when importing models

Handle the ImportError exception when importing models in the lmms_eval package. This change adds a try-except block to catch the ImportError and print an error message indicating the failed import. This will help with troubleshooting and identifying any issues with the model imports.

Author: Luodian

Diff for: lmms_eval/models/__init__.py

@@ -34,5 +34,6 @@
 for model_name, model_class in AVAILABLE_MODELS.items():
     try:
         exec(f"from .{model_name} import {model_class}")
-    except ImportError:
+    except ImportError as e:
+        print(f"Failed to import {model_class} from {model_name}: {e}")
         pass