Add REUSE lint in CI

Author: flashcode

.github/workflows/ci.yml

@@ -34,7 +34,10 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          pip install bandit coverage flake8 mock mypy pylint pytest pytest-cov types-mock
+          pip install bandit coverage flake8 mock mypy pylint pytest pytest-cov reuse types-mock
+
+      - name: Check REUSE compliancy
+        run: reuse lint
 
       - name: Lint with flake8
         run: make flake8