chore(deps): update dependency ubuntu to v26

Author: renovate[bot]

.github/workflows/ci.yml

@@ -4,7 +4,7 @@ on:
   workflow_dispatch:
 jobs:
   check-links:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-26.04
     steps:
     - uses: actions/checkout@v7
     - name: Lychee Broken Link Checker