[core] Setting attributesForFaceting from the config overrides Algolia settings

[s-pace]

Situation

When a configuration includes custom_settings.attributesForFaceting, the index's setting attributesForFaceting does not include tags anymore. This override the default_settings defined by the strategy. tags defined from start_urls are not longer handled as attributesForFaceting

Result:

It might broke the search for owner filtering over tags and break the search. Happens a lot with people using meta tags.

Workaround

Make sure configuration defines tags as a item from the collection custom_settings.attributesForFaceting

[JOHNMDAY-CREATE]

tags

[JOHNMDAY-CREATE]

``` Tags#490