Facet counts not updated

Facet counts are not updated when a facet is selected.

This appears to be the same as issue 2866029 linked below but I can confirm that the patch from that ticket has been applied, the change is in place in the current code base.

Steps to reproduce:

• Install and configure Search API, Elasticsearch connector and Facets module
• Index data (eg. node articles) with at least one string field (Content type is a good one).
• Create a view based on the Index created, and add a filter for Content type, expose it. Add a page display.
• Add a facet for Content Type, ensure "Show the amount of results" is checked so we can see the numbers next to the facet values
• Show the facets somewhere on the search page.
• Notice that when you use the filter, the counts and list of facets are not updated.