[MNT] [Dependabot](deps): Bump actions/cache from 4 to 5 (#614)

Bumps [actions/cache](https://github.com/actions/cache) from 4 to 5.

Author: dependabot[bot]

.github/workflows/testing.yml

@@ -60,7 +60,7 @@ jobs:
         run: uv pip list
 
       - name: Restore test's datasets
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@v5
         with:
           path: tests/.datasets
           key: test-datasets
@@ -69,7 +69,7 @@ jobs:
         run: python -m pytest -v
 
       - name: Save test's datasets
-        uses: actions/cache/save@v4
+        uses: actions/cache/save@v5
         with:
           path: tests/.datasets
           key: test-datasets