doc(readme): add chat badge (#2345)

Add a badge that links to the olm-dev channel in the Kubernetes Slack
instance.

Signed-off-by: Nick Hale <[email protected]>

Author: njhale

README.md

@@ -3,6 +3,7 @@
 [![Container Repository on Quay.io](https://quay.io/repository/operator-framework/olm/status "Container Repository on Quay.io")](https://quay.io/repository/operator-framework/olm)
 [![License](http://img.shields.io/:license-apache-blue.svg)](http://www.apache.org/licenses/LICENSE-2.0.html)
 [![Go Report Card](https://goreportcard.com/badge/github.com/operator-framework/operator-lifecycle-manager)](https://goreportcard.com/report/github.com/operator-framework/operator-lifecycle-manager)
+[![Slack Channel](https://img.shields.io/badge/chat-4A154B?logo=slack&logoColor=white "Slack Channel")](https://kubernetes.slack.com/archives/C0181L6JYQ2)
 
 ## Documentation
 
@@ -191,4 +192,4 @@ Operator Lifecycle Manager is under Apache 2.0 license. See the [LICENSE][licens
 [operator-framework-meetings]: https://github.com/operator-framework/community#meetings
 [contributor-documentation]: https://olm.operatorframework.io/docs/contribution-guidelines/
 [olm-getting-started]: https://olm.operatorframework.io/docs/getting-started/
-[installation-guide]: doc/install/install.md
+[installation-guide]: doc/install/install.md