removed phase banner includes due to component not being tested or released by developer

Author: jakecosgrove

docs/_includes/primary-navigation.html

@@ -9,11 +9,3 @@
     {% endfor -%}
   </ul>
 </nav>
-
-{% include components/phase-banner.html
-auto_hide='true'
-phase_id= 'dev'
-phase_tag= 'Developer'
-phase_text='This is a developer preview of notify.nhs.uk. <a href="https://notify.nhs.uk">Go to the live NHS Notify
-  website.</a>'
-%}