Update error message to unbreak main (#1274)

Update test_base.py

fixing trunk health after this error was updated in core

test/float8/test_base.py

@@ -632,7 +632,7 @@ def test_pad_inner_dim(self, base_dtype, use_fast_accum):
         with pytest.raises(
             RuntimeError,
             match=re.escape(
-                "Expected trailing dimension of mat1 to be divisible by 16 but got mat1 shape: (16x41."
+                "Expected trailing dimension of mat1 to be divisible by 16 but got mat1 shape: (16x41)."
             ),
         ):
             a_fp8 @ b_fp8