Add back checkout Compute step

Author: jcmosc

.github/workflows/swift.yml

@@ -39,3 +39,6 @@ jobs:
           ln -s ../Ninja-RelWithDebInfoAssert/swift-macosx-arm64 build/Default/swift
           ln -s ../Ninja-RelWithDebInfoAssert/llvm-macosx-arm64 build/Default/llvm
         working-directory: ./swift-project
+      - uses: actions/checkout@v4
+        with:
+          path: Compute