Fix nightly workflow definition and add reuse context (#1035)

Author: bergundy

.github/workflows/nightly.yml

@@ -12,3 +12,10 @@ jobs:
     with:
       test-type: ci-nightly
       test-timeout-minutes: 360 # yes, 6 hours
+      reuse-v8-context: false
+  nightly-reuse-context:
+    uses: ./.github/workflows/stress.yml
+    with:
+      test-type: ci-nightly
+      test-timeout-minutes: 360 # yes, 6 hours
+      reuse-v8-context: true