Update cache-dependency-path

Author: matt-graham

.github/workflows/tests.yml

@@ -33,6 +33,9 @@ jobs:
       with:
         python-version: ${{ matrix.python-version }}
         cache: pip
+        cache-dependency-path: |
+          requirements/requirements-core.txt
+          requirements/requirements-tests.txt
     
     - name: Install dependencies
       run: |