Update runs-on property of workflow

Author: Kawron

.github/workflows/ci_build_test.yaml

@@ -23,7 +23,7 @@ permissions:
 jobs:
   workflow_approval:
     name: Approve workflow
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     environment: workflow-approval
     steps:
       - name: Approve workflow
@@ -88,7 +88,7 @@ jobs:
 
   build-unit-test:
     name: build and run unit test
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     needs:
       - workflow_approval
     steps:
@@ -122,7 +122,7 @@ jobs:
 
   e2e_test:
     name: e2e test - kafka version-${{ matrix.kafka_version }}
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     needs:
       - build-unit-test
     strategy: