feat: added Discord link to sidebar

[GreenFlux]

Description

Several users have failed to find the Discord and have complained on Reddit of lack of support. Adding Discord link to sidebar to make it more visible than having to visit support page first.

Pull request type

Check the appropriate box:

• [ ] Review Fixes
• [ ] Documentation Overhaul
• [ ] Feature/Story
  • Link one or more Engineering Tickets *
• [ ] A-Force
• [ ] Error in documentation
• [x] Maintenance

Documentation tickets

Link to one or more documentation tickets:

Checklist

From the below options, select the ones that are applicable:

• [ ] Checked for Grammarly suggestions.
• [ ] Adhered to the writing checklist.
• [ ] Adhered to the media checklist.
• [ ] Verified and updated cross-references or added redirect rules.
• [ ] Tested the redirect rules on deploy preview.
• [ ] Validated the modifications made to the content on the deploy preview.
• [ ] Validated the CSS modifications on different screen sizes.