Fix validation errors in plugin documentation (#399) (#458)

[backport/2.2] Fix validation errors in plugin documentation (#399)

Fix validation errors in plugin documentation
SUMMARY
This fixes validation errors in plugin documentation now that ansible
test for 2.13 is running validate-modules on all plugins. The kubectl
connection plugin validation is ignored because there seems to be a
requirement for the author field to have a github username, which we do
not have.
ISSUE TYPE
Docs Pull Request
COMPONENT NAME
plugins/connection/kubectl
plugins/inventory/k8s
plugins/lookup/k8s
plugins/lookup/kustomize
ADDITIONAL INFORMATION
Reviewed-by: None 
(cherry picked from commit 30e84fa)

plugins/connection/kubectl.py

@@ -22,9 +22,9 @@ __metaclass__ = type
 
 DOCUMENTATION = r"""
     author:
-        - xuxinkun
+        - xuxinkun (@xuxinkun)
 
-    connection: kubectl
+    name: kubectl
 
     short_description: Execute tasks in pods running on Kubernetes.