Update test user name and delete task

- Gives the user a name identifiable as a QA test user.
- Includes the original name in the delete task.

qa/qa/specs/features/browser_ui/2_plan/issue/check_mentions_for_xss_spec.rb

@@ -4,7 +4,7 @@ module QA
   RSpec.describe 'Plan', :reliable do
     let!(:user) do
       Resource::User.fabricate_via_api! do |user|
-        user.name = "eve <img src=x onerror=alert(2)&lt;img src=x onerror=alert(1)&gt;"
+        user.name = "QA User <img src=x onerror=alert(2)&lt;img src=x onerror=alert(1)&gt;"
         user.password = "test1234"
         user.api_client = Runtime::API::Client.as_admin
       end

qa/qa/tools/delete_test_users.rb

@@ -53,6 +53,11 @@ module QA
         # When we reach the last page, the x-next-page header is a blank string
         @page_no = response.headers[:x_next_page].to_s
 
+        if @page_no.to_i > 1000
+          puts "Finishing early to avoid timing out the CI job"
+          exit
+        end
+
         JSON.parse(response.body).select do |user|
           user['username'].start_with?('qa-user-', 'test-user-') \
             && (user['name'] == 'QA Tests' || user['name'].start_with?('QA User')) \