Remove non-super sidebar related code for trial status widget/popover

The following discussion from !151448 (merged) should be addressed:

• @dstull started a discussion:

  note (non-blocking):

  The initialization of the widget and popover can be removed once super sidebar is fully cutover.

• confirmation - #458815 (comment 1886211505). We can remove the non-super sidebar calls.

Plan

• remove code in javascript initializers and calls:
  • ee/app/assets/javascripts/contextual_sidebar/init_trial_status_widget_and_popover.js and all calls using it.
  • could be more intertwined with this...
• remove code in ruby and calls to it:
  • ee/app/views/layouts/nav/sidebar/_group_trial_status_widget.html.haml
  • ee/lib/sidebars/groups/menus/trial_widget_menu.rb
  • ee/lib/sidebars/projects/menus/trial_widget_menu.rb
  • could be more intertwined with this...