Adding weekly call information (#9)

Signed-off-by: Chris Hein <[email protected]>

Author: christopherhein

README.md

@@ -8,8 +8,12 @@ Learn how to engage with the Kubernetes community on the [community page](http:/
 
 You can reach the maintainers of this project at:
 
-- [Slack](https://kubernetes.slack.com/messages/sig-cluster-lifecycle)
+- [Slack](https://kubernetes.slack.com/messages/cluster-api-nested)
 - [Mailing List](https://groups.google.com/forum/#!forum/kubernetes-sig-cluster-lifecycle)
+- Join our Cluster API Provider Nested working group sessions
+  - Weekly on Tuesdays @ 10:00 PT
+  - Previous meetings:
+    [notes](https://docs.google.com/document/d/10aTeq2lhXW_3aFQAd_MdGjY8PtZPslKhZCCcXxFp3_Q/edit#)
 
 ### Code of conduct