FE for share groups with groups

What does this MR do?

#22986 (closed)

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• [-] Separation of EE specific content

Performance and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

app/controllers/groups/group_links_controller.rb

@@ -3,6 +3,7 @@
 class Groups::GroupLinksController < Groups::ApplicationController
   before_action :check_feature_flag!
   before_action :authorize_admin_group!
+  before_action :group_link, only: [:update, :destroy]
 
   def create
     shared_with_group = Group.find(params[:shared_with_group_id]) if params[:shared_with_group_id].present?
@@ -23,13 +24,11 @@ def create
   end
 
   def update
-    link = group.shared_with_group_links.find(params[:id])
-    link.update(group_link_params)
+    @group_link.update(group_link_params)
   end
 
   def destroy
-    link = group.shared_with_group_links.find(params[:id])
-    Groups::GroupLinks::DestroyService.new(nil, nil).execute(link)
+    Groups::GroupLinks::DestroyService.new(nil, nil).execute(@group_link)
 
     respond_to do |format|
       format.html do
@@ -41,6 +40,10 @@ def destroy
 
   private
 
+  def group_link
+    @group_link ||= group.shared_with_group_links.find(params[:id])
+  end
+
   def group_link_create_params
     params.permit(:shared_group_access, :expires_at)
   end