Update sig-etcd charter to link to etcd's GOVERNANCE.md

Signed-off-by: Benjamin Wang <[email protected]>

Author: ahrtr

sig-etcd/charter.md

@@ -46,8 +46,10 @@ and opts-in to updates and modifications to [sig-governance].
   - Email: [etcd-dev](https://groups.google.com/forum/?hl=en#!forum/etcd-dev).
   - Slack: [#etcd](https://kubernetes.slack.com/messages/C3HD8ARJ5/details/) channel on Kubernetes.
 - SIG etcd contributing instructions ([CONTRIBUTING.md]) be defined in etcd project.
+- SIG etcd governance instructions ([GOVERNANCE.md]) be defined in etcd project.
 
 [CONTRIBUTING.md]: https://github.com/etcd-io/etcd/blob/main/CONTRIBUTING.md
+[GOVERNANCE.md]: https://github.com/etcd-io/etcd/blob/main/GOVERNANCE.md
 
 ### Deviations from [kubernetes-repositories]