[BUG] Discord invite link broken on README.md

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• [x] I have searched for similar issues in both open and closed tickets and cannot find a duplicate.
• [x] I have read the documentation and cannot find an answer.

Describe the bug Discord link in README.md is broken.

To Reproduce Steps to reproduce the behavior:

1. Go to repository home page
2. Scroll down to the readme section
3. Click link 'join our Discord Server'
4. See 'Invite Invalid' error page

Expected behavior You should be able to join the Discord server

Additional context Someone with admin privileges on the Discord server will have to create a new link without an expiry date.