Fix community Slack link in README
Closes from autumnust/fix_slack_link
[![Documentation Status](https://readthedocs.org/projects/gobblin/badge/?version=latest)](https://gobblin.readthedocs.org/en/latest/?badge=latest)
[![Maven Central](https://maven-badges.herokuapp.com/maven-central/org.apache.gobblin/gobblin-api/badge.svg)](https://search.maven.org/search?q=g:org.apache.gobblin)
[![Stack Overflow](http://img.shields.io/:stack%20overflow-gobblin-brightgreen.svg)](http://stackoverflow.com/questions/tagged/gobblin)
-[![Join us on Slack](https://img.shields.io/badge/slack-apache--gobblin-brightgreen.svg)](https://communityinviter.com/apps/apache-gobblin/apache-gobblin)
+[![Join us on Slack](https://img.shields.io/badge/slack-apache--gobblin-brightgreen.svg)]( https://join.slack.com/t/apache-gobblin/shared_invite/zt-vqgdztup-UUq8S6gGJqE6L5~9~JelNg)
[![codecov.io](https://codecov.io/github/apache/gobblin/branch/master/graph/badge.svg)](https://codecov.io/github/apache/gobblin)
Apache Gobblin is a highly scalable data management solution for structured and byte-oriented data in heterogeneous data ecosystems.
@@ -60,7 +60,7 @@ The distribution will be created in build/gobblin-distribution/distributions dir
* [Running Gobblin on Docker from your laptop](https://github.com/apache/gobblin/blob/master/gobblin-docs/user-guide/Docker-Integration.md)
* [Getting started guide](https://gobblin.apache.org/docs/Getting-Started/)
* [Gobblin architecture](https://gobblin.apache.org/docs/Gobblin-Architecture/)
- * Community Slack: [Get your invite](https://communityinviter.com/apps/apache-gobblin/apache-gobblin)
+ * Community Slack: [Get your invite]( https://join.slack.com/t/apache-gobblin/shared_invite/zt-vqgdztup-UUq8S6gGJqE6L5~9~JelNg)
* [List of companies known to use Gobblin](https://gobblin.apache.org/docs/Powered-By/)
* [Sample project](https://github.com/apache/gobblin/tree/master/gobblin-example)
* [How to build Gobblin from source code](https://gobblin.apache.org/docs/user-guide/Building-Gobblin/)
