docs: Visual Studio repo, remove beta info

Removes the beta-related language in prep for the 2023-12-21 GA.

I have two questions, and to be safe I'm blocking merge until I can get answers from @john-slaughter.

ALSO: This merge request uses GitLab repo: change Code Suggestion to GA (gitlab-org/gitlab!139770 - merged) as a blocker to ensure we do not merge changes to the groupeditor extensions repos until after the changes to the gitlab repo are merged.

Related items

• Related to Remove Beta labeling for Code Suggestions settings (&19 - closed)
• Related to Remove GitLab SaaS Beta label from documentation (gitlab-org/gitlab#435271 - closed)