add isort workflow

.github/workflows/isort.yml

@@ -0,0 +1,27 @@
+name: Run isort
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Check out source-code repository
+        uses: actions/checkout@v2
+
+      - name: Set up Python 3.9
+        uses: actions/setup-python@v2
+        with:
+          python-version: 3.9
+
+      - name: Install python dependencies
+        run: |
+          python -m pip install --upgrade pip -r requirements-dev.txt
+          pip install -e .
+
+      - name: Install isort
+        run: pip install isort
+
+      - uses: jamescurtin/isort-action@master
+        with:
+          configuration: "--profile black"
+          requirementsFiles: "requirements.txt requirements-dev.txt"