Fix slack links

Author: iraola

README.md

@@ -31,7 +31,7 @@
     <a href="https://dislib.bsc.es">Website</a> •
     <a href="https://dislib.bsc.es/en/stable/api-reference.html">Documentation</a> •
     <a href="https://github.com/bsc-wdc/dislib/releases">Releases</a> •
-    <a href="https://bit.ly/bsc-wdc-community">Slack</a>
+    <a href="https://bsc-wdc.slack.com/archives/CFGD3K8BG">Slack</a>
 </b></p>
 
 ## Introduction

docs/source/index.rst

@@ -84,7 +84,7 @@ Support
 -------
 
 If you have questions or issues about the dislib you can join us in `Slack
-<https://bit.ly/bsc-wdc-community>`_.
+<https://bsc-wdc.slack.com/archives/CFGD3K8BG>`_.
 
 Alternatively, you can send us an e-mail to `[email protected]
 <mailto:[email protected]>`_.