Remove the lint tests because they are using python2 (#728)

* Lint is failing because we are still runing python2 for lint

* kubeflow/testing#560 is related to building an updated image with python3.8
  compatible version of lint so we can support f style strings.

* However, the unittests for kubeflow examples are still written in
  ksonnet. Its not worth trying to update that so we just
  remove that test for now. The test was just running lint

* We should really see about using Tekton to write the workflows

  see kubeflow/testing#425

prow_config.yaml

@@ -3,14 +3,6 @@
 python_paths:
   - kubeflow/examples/py
 workflows:
-  - app_dir: kubeflow/examples/test/workflows
-    component: workflows
-    name: unittests
-    job_types:
-    - presubmit
-    - postsubmit
-    - periodic
-
   # E2E test for code_search example
   - app_dir: kubeflow/examples/test/workflows
     component: code_search