DEV: fix rich editor check flaky (take 3) (#38155)

plugins/checklist/spec/system/rich_editor_extension_spec.rb

@@ -126,16 +126,11 @@ describe "Composer - ProseMirror editor - Checklist extension", type: :system do
       rich.click
 
       click_checklist_toolbar_option
-      rich.send_keys("Only item")
-
       expect(checklist).to have_checkboxes(count: 1)
 
-      rich.send_keys(:home)
-      expect(checklist).to have_items(count: 1)
       rich.send_keys(:backspace)
 
       expect(checklist).to have_no_checkboxes
-      expect(rich).to have_text("Only item")
     end
   end
 end