Tests - Update groups fabrication via UI

What does this MR do and why?

Search field was removed for dashboard/groups page in case there are no groups, aka 'empty state' - !162034 (merged).

This MR is to update the tests to handle empty state for dashboard/groups properly. Essentially return false for has_group? method when a user has no groups.

This should fix the following tests that we see failing on Staging:

• https://gitlab.com/gitlab-org/gitlab/-/issues/478450
• https://gitlab.com/gitlab-org/gitlab/-/issues/478451
• https://gitlab.com/gitlab-org/gitlab/-/issues/478462
• https://gitlab.com/gitlab-org/gitlab/-/issues/478452
• https://gitlab.com/gitlab-org/gitlab/-/issues/478446
• https://gitlab.com/gitlab-org/gitlab/-/issues/478447

MR acceptance checklist

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

Screenshots or screen recordings

Tests that were failing before are passing locally when run against Staging:

How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

Run the tests agains Staging, e.g. (Make sure to set GITLAB_QA_USER_AGENT, GITLAB_ADMIN_USERNAME, GITLAB_ADMIN_PASSWORD, GITLAB_QA_ADMIN_ACCESS_TOKEN env variables):

QA_GITLAB_URL=https://staging.gitlab.com bundle exec rspec qa/specs/features/ee/browser_ui/11_fulfillment/saas_user_limit_experience_spec.rb