[TASK] Remove unused template file for old pagetree

When removing the deprecated alt_db_navframe code
the HTML template file was not removed.

Resolves: #72641
Releases: master
Change-Id: Iafb3197e9fb351db885d2c1177395e8c671bf306
Reviewed-on: https://review.typo3.org/45820


Reviewed-by: Wouter Wolters <typo3@wouterwolters.nl>
Tested-by: Wouter Wolters <typo3@wouterwolters.nl>
Reviewed-by: Georg Ringer <georg.ringer@gmail.com>
Tested-by: Georg Ringer <georg.ringer@gmail.com>