chore(deps)!: update actions/cache (v4 → v5)

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

.github/workflows/ci.yaml

@@ -20,7 +20,7 @@ jobs:
           go-version-file: "go.mod"
 
       - name: Cache Go build
-        uses: actions/cache@v4
+        uses: actions/cache@cdf6c1fa76f9f475f3d7449005a359c84ca0f306 # v5
         with:
           path: |
             ~/.cache/go-build