Show extensions marketplace disabled message when enterprise group disabled

MR: feat: Add message for marketplace disabled by e... (!363 - merged)

Description

Related to Update extensions marketplace metadata logic to... (gitlab#474154 - closed).

If the extensionsGallerySettings.reason is enterprise_group_disabled then we want to show a helpful message.

Acceptance Criteria

  • Web IDE shows a helpful message when the extensions gallery is disabled for this reason.
  • The message includes a helpful link to the relevant enterprise group and a link to the docs for resolving the issue.
  • The @gitlab/web-ide package in the main GitLab project is updated to include the release with these changes.
Edited by Paul Slaughter