Remove "Details" from breadcrumb and JSON+JD on Group top page

What does this MR do?

Removes "Details" from breadcrumb and JSON+JD on Group (top-level and sub-) top page.

Relates to !47817 (merged) (for Project)

Screenshots (strongly suggested)

Before	After
TBD

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• [n/a] Documentation (if required)
• Code review guidelines
• [n/a] Merge request performance guidelines
• Style guides
• Separation of EE specific content

Related to #284008 (closed)

app/views/groups/show.html.haml

-- breadcrumb_title _("Details")
 - @content_class = "limit-container-width" unless fluid_layout
 - page_itemtype    'https://schema.org/Organization'
+- @skip_current_level_breadcrumb = true
 
 - if show_thanks_for_purchase_banner?
   = render_if_exists 'shared/thanks_for_purchase_banner', plan_title: plan_title, quantity: params[:purchased_quantity].to_i