chore(deps): update actions/cache action to v5

.gitea/workflows/otf-apply.yml

@@ -76,7 +76,7 @@ jobs:
           known-hosts: ${{ secrets.ssh-known-hosts }}
       - name: Restore tofu cache
         if: ${{ steps.check.outputs.code == 2 }}
-        uses: actions/cache@v4
+        uses: actions/cache@v5
         id: cache-tofu-restore
         with:
           path: .terraform
@@ -96,7 +96,7 @@ jobs:
         run: tofu apply -input=false -auto-approve tfplan.binary;
       - name: Save tofu cache
         if: ${{ steps.check.outputs.code == 2 }}
-        uses: actions/cache/save@v4
+        uses: actions/cache/save@v5
         id: cache-tofu-save
         with:
           path: .terraform