change ubuntu version for linter workflow

Author: barha-jit

.github/workflows/linter.yml

@@ -7,7 +7,7 @@ on:
       - '!main'
 jobs:
   linter:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3
     - name: Set up Python 3.8