Make ExecuTorch build with Xcode 26 beta toolchain and InferSendableFromCaptures enabled

Summary:
Fix a bunch of staging builds that stopped working after enabling `InferSendableFromCaptures` globally. This is likely caused by a bug in Xcode's 26 toolchain, although I've not been able to reproduce it in an isolated sample.

Switching from `Array.init` to `{ Array($0) }` solves the issue and keeps the code building without warnings in all toolchain versions.

Differential Revision: D78406265

Author: Xavier Jurado Cristobal

extension/apple/ExecuTorch/Exported/ExecuTorch+Tensor.swift

@@ -832,7 +832,7 @@ public extension Tensor {
   /// - Returns: An array of scalars of type `T`.
   /// - Throws: An error if the underlying data cannot be accessed.
   func scalars() throws -> [T] {
-    try withUnsafeBytes(Array.init)
+    try withUnsafeBytes { Array($0) }
   }
 }