GitHub action updated

Updated the Ubuntu image for GH action runner
from 20.04 to latest

Author: devdattakulkarni

.github/workflows/pr-minikube.yaml

@@ -7,7 +7,7 @@ env:
   KUBEPLUS_TEST_OUTPUT: yes
 jobs:
   job1:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     name: Deploy to minikube
     steps:
     - uses: actions/checkout@v2

.github/workflows/pr.yaml

@@ -11,7 +11,7 @@ env:
   KUBEPLUS_CI: true
 jobs:
   job1:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-latest
     name: Test kubeplus deployment on kind
     steps:
     - name: Checkout Code