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

Author: renovate[bot]

.github/workflows/links.yml

@@ -13,7 +13,7 @@ jobs:
     steps:
       - uses: actions/checkout@v5
 
-      - uses: actions/cache@v4
+      - uses: actions/cache@v5
         with:
           path: .lycheecache
           key: cache-lychee-${{ github.sha }}