Improve skipped billing page hand raise spec

What does this MR do and why?

Improve skipped billing page hand raise spec

1. Fix ids for the hand raise vue form
2. Unskip the test
3. Make sure we're testing groups and personal namespaces differently
4. Test for the prefilled values for the form

Followup for !72014 (diffs) related to #342727 (closed)

How to test locally

  bin/rspec -fd ./ee/spec/features/billings/billing_plans_spec.rb -e "displays the in-app hand raise lead"

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