fix: CMD-176 conditional elastic search

[wesleyboar]

Overview

• Make automatic search index conditional.
• Always support Elasticsearch.

Related

• CMD-176
• fixes feat: support disabling elasticsearch #834
• required by feat(ecep): CMD-176 conditional elastic search Core-CMS-Custom#300

Changes

• documented setting rename
• removed conditionals from _settings/search.py
• moved aldryn_apphooks_config to INSTALLED_APPS
• refactored PORTAL_ES_ENABLED as PORTAL_SEARCH_INDEX_IS_AUTOMATIC

Testing

• ✅ Verify site using Elasticsearch can still:
  ^{Tested on https://dev.cep.tacc.utexas.edu/.}
  • Publish pages.
  • Search page content (via Portal).
• ✅ Verify site using Google search can still:
  ^{Tested on https://pprd.ecep.tacc.utexas.edu/.}
  • Publish pages.
  • Search page content (via Google).
• ✅ Verify site not using any search can still:
  ^{Tested on https://pprd.wtcs.tacc.utexas.edu/.}
  • Publish pages.

UI

Skipped.