ci: Update ubuntu version for coverage

Author: GrayJack

.github/workflows/coverage.yml

@@ -21,7 +21,7 @@ on:
 
 jobs:
   coverage:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     if: ${{ (github.event_name == 'pull_request' && github.event.pull_request.head.repo.fork) || github.event_name == 'push' }}
 
     steps: