[mod] settings.yml: remove plugin settings for plugins that don't exist anymore

utils/templates/etc/searxng/settings.yml

@@ -33,14 +33,11 @@ ui:
 
 enabled_plugins:
   - 'Hash plugin'
-  - 'Search on category select'
   - 'Self Informations'
   - 'Tracker URL remover'
   - 'Ahmia blacklist'
   # - 'Hostname replace'  # see hostname_replace configuration below
-  # - 'Infinite scroll'
   # - 'Open Access DOI rewrite'
-  # - 'Vim-like hotkeys'
 
 # plugins:
 #   - only_show_green_results