Added isort check in workflow config

Author: akash-suresh

.github/workflows/config.yml

@@ -49,6 +49,10 @@ jobs:
       run: |
         python -m pip install mypy
         python run_mypy.py
+    - name: Check imports are sorted
+      run: |
+        python -m pip install isort
+        python -m isort --check-only
     - name: Check that all strategies are indexed
       run: |
         python run_strategy_indexer.py