Add alter hook to reset_entity_panelizer function

Problem/Motivation

This patch is in support of the Authcache Support Panelizer patch: https://www.drupal.org/project/authcache/issues/2703789

After testing the latest version of the Authcache patch, it became clear it was necessary to rebuild Authcache personalization fragments when a page reset is done for an overridden Panelizer page. If the rebuild is not performed, the data stored for Authcache becomes out of sync with what would be expected on the site.

Initially, we attempted to avoid a Panelizer patch by extending the PanelizerEntityDefault class. However, that is not possible since Panelizer classes are not extendable by other modules. The attached patch resolves the problem.

Steps to reproduce

Perform a page reset of a Panelizer page with panes that are cached using Authcache p13n. Examine Authcache p13n settings in the admin dashboard.

Proposed resolution

See attached patch.

Remaining tasks

Review attached patch. I would appreciate any feedback, thanks.