Use hashed requirements lock

.github/workflows/dependency-audit.yml

@@ -19,7 +19,9 @@ jobs:
       - name: Install dependencies
         run: |
           python -m pip install --upgrade pip
-          pip install -r src/requirements.txt
-          pip install pip-audit
+          pip install pip-tools pip-audit
+          pip-compile --generate-hashes --output-file=requirements.lock src/requirements.txt
+          git diff --exit-code requirements.lock
+          pip install --require-hashes -r requirements.lock
       - name: Run pip-audit
         run: pip-audit -r requirements.lock --ignore-vuln GHSA-wj6h-64fc-37mp