Validate dependency files are in sync

Only check on one version of Python as they're likely to be version
specific. Pick 3.10 to check on as that's the platform they currently
claim to be built for.

.github/workflows/test.yml

@@ -35,6 +35,13 @@ jobs:
       - name: Install dependencies
         run: pip install -r requirements.txt -r requirements-dev.txt
 
+      - name: Validate dependencies
+        uses: PeterJCLaw/validate-generated-files@v1
+        if: matrix.python == '3.10'
+        with:
+          command: ./script/compile-requirements.sh
+          files: requirements*.txt
+
       - name: Use the dev configuration
         run: cp helpdesk/helpdesk/configuration.dev.py helpdesk/helpdesk/configuration.py