Fix test util

`torch_use_tf32_matmul` should reset to original setting when there is
exception.

Signed-off-by: Jay Gu <jagu@nvidia.com>

Author: haijieg

test/util.py

@@ -219,8 +219,10 @@ def next_power_of_2(n: int):
 def torch_use_tf32_matmul():
     origin = torch.backends.cuda.matmul.fp32_precision
     torch.backends.cuda.matmul.fp32_precision = "tf32"
-    yield
-    torch.backends.cuda.matmul.fp32_precision = origin
+    try:
+        yield
+    finally:
+        torch.backends.cuda.matmul.fp32_precision = origin
 
 
 def get_compute_capability_major():