GH actions: use ubuntu-latest instead of ubuntu-20.04

.github/workflows/main.yml

@@ -7,7 +7,7 @@ on:
 
 jobs:
   build-and-deploy:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     permissions:
       pull-requests: read # Get the list and metadata of open new-rule PRs
       contents: write # Get the contents of open new-rule PRs, the 'master'; write to 'gh-pages' branch

.github/workflows/update_quickfix_status.yml

@@ -25,7 +25,7 @@ on:
 jobs:
   update_quickfix_status:
     name: Update quick fix status
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     permissions:
       contents: write
       pull-requests: write