Use isolated test runner in deploy workflow

- Update deploy CI to invoke `shared/scripts/test-isolated.sh`
- Refresh the inline note for the test environment setup

.github/workflows/deploy.yml

@@ -86,7 +86,7 @@ jobs:
 
       - name: Run Tests
         run: |
-          # Create .env.test for test-sequential.sh / bun test
+          # Create .env.test for the isolated test runner / bun test
           cat <<EOF > .env.test
           DATABASE_URL="postgresql://postgres:postgres@postgres:5432/aurora_test"
           DISCORD_BOT_TOKEN="test_token"
@@ -95,6 +95,6 @@ jobs:
           ADMIN_TOKEN="admin_token_123"
           LOG_LEVEL="error"
           EOF
-          bash shared/scripts/test-sequential.sh --integration
+          bash shared/scripts/test-isolated.sh --integration
         env:
           NODE_ENV: test