DOC-2399: Update Basic Setup section in AI Assistant plugin page

[FarzadHayat]

Ticket: DOC-2399

Site: Staging branch

Hotfix - I forgot to update the "Basic setup" section with the initial pull request.

Changes:

• DOC-2399: Update Basic Setup section in AI Assistant plugin page

Pre-checks:

• [x] Branch prefixed with feature/<version>/, hotfix/<version>/, staging/<version>/, or release/<version>/
• [-] modules/ROOT/nav.adoc has been updated (if applicable)
• [-] Files has been included where required (if applicable)
• [-] Files removed have been deleted, not just excluded from the build (if applicable)
• [-] Files added for New product features, and included a release note entry.

Review:

• [x] Documentation Team Lead has reviewed