[PyTorch] Pass c10::optional<bool> to Stride ctor by value (pytorch#6…

…6698)

Summary:
Pull Request resolved: pytorch#66698

this type should fit in a register; no need to pass by reference.
ghstack-source-id: 140742830

Test Plan: CI

Reviewed By: suo

Differential Revision: D31693291

fbshipit-source-id: 299fb3d1830a059b59268487c22e030446c3496e

aten/src/ATen/core/jit_type.h

@@ -243,7 +243,7 @@ struct TORCH_API Stride {
   Stride() {}
   Stride(
       const c10::optional<size_t>& stride_index,
-      const c10::optional<bool>& contiguous,
+      c10::optional<bool> contiguous,
       const c10::optional<size_t>& stride)
       : stride_index_(stride_index), contiguous_(contiguous), stride_(stride) {}