[VS Code] Onboarding link for Code Suggestions is broken

Checklist

• I'm using the latest version of the extension (see the latest version in the right column of this page)
  • Extension version: Put your extension version here
• I'm using the latest VS Code version (find the latest version here)
  • VS Code version: Put your VS Code version here
• I'm using a supported version of GitLab (see README for the supported version)
  • GitLab version: happens on gitlab.com

Summary

For new users we display a message inviting them to read the docs for Code Suggestions, but the link provided leads to a 404.

Steps to reproduce

When getting the welcome message for Code Suggestions, click on "Learn more"

What is the current bug behavior?

A non-existing page opens in the browser

What is the expected correct behavior?

The relevant help page opens

Relevant logs and/or screenshots

Possible fixes

Update the URL at https://gitlab.com/gitlab-org/gitlab-vscode-extension/-/blob/76b4af4000fb66dbff5f98318e58512ed707392a/src/desktop/code_suggestions_promo.ts#L6