First iteration for enhanced add code task to get started

What does this MR do and why?

First iteration for enhanced add code task to get started

• add enhanced instructions except for command line modal(will be delivered in follow-up MR to keep size lower in this MR)
• add tracking
• remove the repo action to focus the user on adding code
• all events verified in snowplow extension in browser as per spec
• see https://gitlab.com/gitlab-org/gitlab/-/issues/556427

Changelog: other EE: true

Screenshots or screen recordings

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state	Before	After
uncompleted
upload modal	net new - NA
completed

How to set up and validate locally

Note: This is covered by feature spec in this MR and jest as much as possible.

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1. Setup gdk to simulate SaaS - https://docs.gitlab.com/ee/development/ee_features.html#simulate-a-saas-instance and restart GDK
2. Create a new group and project.
3. In rails console, onboard that group that was just created

   ::Onboarding::Progress.onboard(Group.last)

4. In the gitlab admin UI, edit the group to be on an ultimate trial plan(edit button from http://gdk.test:3000/admin/groups)
5. In rails console(bundle exec rails c), change the trial, trial start and end date for the group

   Group.last.gitlab_subscription.update_columns(trial_starts_on: Date.today, trial_ends_on: 30.days.from_now, trial: true)

6. Go to the get started path for the group/project: For instance, http://gdk.test:3000/logan225-group/logan225-project/-/get_started

MR acceptance checklist

Evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Related to #556427