Add link to lightkube in Community-maintained client libraries.

Author: gtsystem

content/en/docs/reference/using-api/client-libraries.md

@@ -67,6 +67,7 @@ their authors, not the Kubernetes team.
 | PHP                  | [github.com/travisghansen/kubernetes-client-php](https://github.com/travisghansen/kubernetes-client-php) |
 | PHP                  | [github.com/renoki-co/php-k8s](https://github.com/renoki-co/php-k8s) |
 | Python               | [github.com/fiaas/k8s](https://github.com/fiaas/k8s) |
+| Python               | [github.com/gtsystem/lightkube](https://github.com/gtsystem/lightkube) |
 | Python               | [github.com/mnubo/kubernetes-py](https://github.com/mnubo/kubernetes-py) |
 | Python               | [github.com/tomplus/kubernetes_asyncio](https://github.com/tomplus/kubernetes_asyncio) |
 | Python               | [github.com/Frankkkkk/pykorm](https://github.com/Frankkkkk/pykorm) |