Slack link has expired

[mahakg290399]

Describe the bug
The slack link to have a conversation with the developers, is not working. Maybe it is expired

To Reproduce
Steps to reproduce the behavior:

1. Go to 'documentation'
2. Click on 'Jiin slack'
3. See error in your browser

Expected behavior
After clicking on the link, it should forward you to join page on slack

Screenshots
If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context
Add any other context about the problem here.

[chenliu0831]

Yeah there's no plan to bring it back. Use https://github.com/awslabs/python-deequ for now and we will remove the reference from readme.