[e2e] : Change default to fx_importer.

Author: sahas3

projects/pt1/e2e_testing/main.py

@@ -86,7 +86,7 @@ def _get_argparse():
         "-c",
         "--config",
         choices=config_choices,
-        default="linalg",
+        default="fx_importer",
         help=f"""
 Meaning of options:
 "linalg": run through torch-mlir"s default Linalg-on-Tensors backend.