add k8s 1.16 to integration tests

Author: pepov

.circleci/config.yml

@@ -136,6 +136,12 @@ jobs:
           name: Run verification
           command: make
 
+  integration-test-k8s1-16:
+    <<: *integration-test-base
+    environment:
+      <<: *integration-test-environment
+      K8S_VERSION: v1.16.4
+
   integration-test-k8s1-15:
     <<: *integration-test-base
     environment:
@@ -171,6 +177,9 @@ workflows:
   ci:
     jobs:
       - check
+      - integration-test-k8s1-15:
+          requires:
+            - check
       - integration-test-k8s1-15:
           requires:
             - check