A modal is added to edit the realm linkifier which
supports ui_report error.
Puppeteer tests to verify linkifier update and an
invalid test to verify that linkifier error messages
are reported on the modal are added as well.
Moved `admin_settings_modals` template to `/templates/settings/` folder as
earlier, it was inaccurately placed within the `/templates` folder
and should have been within the `/templates/settings` folder.
aryanshridhar
akshatdalton