Merge pull request #230 from GOODBOY008/hotfix

ci: update GitHub Actions to use ubuntu-latest

Author: heqingpan

.github/workflows/mdbook.yml

@@ -10,7 +10,7 @@ on:
 
 jobs:
   deploy:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     concurrency:
       group: ${{ github.workflow }}-${{ github.ref }}
     steps: