Add Dynamic Element Validation to Snippet/Edit

https://gitlab.com/gitlab-org/gitlab/-/issues/257877

qa/qa/page/component/snippet.rb

@@ -139,7 +139,7 @@ module QA
         end
 
         def click_edit_button
-          click_element(:snippet_action_button, action: 'Edit')
+          click_element(:snippet_action_button, Page::Dashboard::Snippet::Edit, action: 'Edit')
         end
 
         def click_delete_button

qa/qa/page/dashboard/snippet/edit.rb

@@ -6,11 +6,10 @@ module QA
       module Snippet
         class Edit < Page::Base
           view 'app/assets/javascripts/snippets/components/edit.vue' do
-            element :submit_button
+            element :submit_button, required: true
           end
 
           def add_to_file_content(content)
-            finished_loading?
             text_area.set content
             text_area.has_text?(content) # wait for changes to take effect
           end