test workspace fix

Author: rnro

.github/workflows/pull_request.yml

@@ -47,7 +47,7 @@ jobs:
   integration-test:
     name: Integration test
     needs: construct-integration-test-matrix
-    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@main
+    uses: apple/swift-nio/.github/workflows/swift_test_matrix.yml@matrix_mark_workspace_safe
     with:
       name: "Integration test"
       matrix_string: '${{ needs.construct-integration-test-matrix.outputs.integration-test-matrix }}'