[Pytorch] Add inductor/test_kernel_benchmark.py to default test suite and update PyTorch pin (#3504)

Part of #3597

Commit:
pytorch/pytorch@a8e3d19

---------

Signed-off-by: Anatoly Myachev <[email protected]>

Author: anmyachev

.github/pins/pytorch.txt

@@ -1 +1 @@
-c21dc11a179b2714509cd901483138adacdce212
+a8e3d1984a78495832d6baca6aa1d95dddc5614a

.github/workflows/inductor-tests.yml

@@ -11,6 +11,7 @@ on:
         description: Space separated lists of test suites or "all"
         type: string
         default: >-
+          inductor/test_kernel_benchmark.py
           inductor/test_codegen_triton.py
           inductor/test_triton_extension_backend.py
           inductor/test_triton_heuristics.py