Revert "add dummy workflow to test GitHub Actions CI (#2697)" (#2698)

This reverts commit cd4761f4.

.github/workflows/test-workflow.yml

-name: scheduled-tests
-
-on:
-  schedule:
-    - cron: "*/30 * * * *"
-
-jobs:
-  download:
-    runs-on: ubuntu-latest
-
-    steps:
-      - name: Set up python
-        uses: actions/setup-python@v2
-        with:
-          python-version: 3.6
-
-      - name: Upgrade pip
-        run: python -m pip install --upgrade pip
-
-      - name: Install PyTorch for CPU from the nightlies
-        run: |
-          pip install numpy
-          pip install --pre torch torchvision -f https://download.pytorch.org/whl/nightly/cpu/torch_nightly.html
-
-      - name: Install test requirements
-        run: pip install pytest pytest-subtests
-
-      - name: Simulate failing tests
-        run: exit 1
-
-      - name: Create issue for failed workflow
-        if: failure()
-        run: echo "Create an issue referencing this workflow run"