Update the name of our Slack channel

[petronbot]

Description

Our channel name on Slack has changed, so they should be updated in UI Kit docs as well.

Definition of Done

• [x] Content/documentation reviewed by Julian or someone in the Content Team
• [x] Code reviewed by one of the core developers
• [x] Stakeholder/PO review
• [x] CHANGELOG updated

[klepas]

LGTM.

[petronbot]

@klepas Do you think this change needs a content review, or should I go ahead and merge?

[klepas]

@petronbot Nah yea, let’s merge; looks fine to me ^_^

[klepas]

@joolswood Can I merge?

[joolswood]

@klepas LGTM