[Fixes #11102] Faceting: prefiltering

[etj]

See #11102

Adjust the count of resources for facets according to filters already applied.

Filters are applied to facets and to facets/<facet_name> results by adding one or more filter{FIELD_EXPR}=VALUE query params.

Checklist

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[codecov]

Codecov Report

Merging #11205 (63aedd7) into master (8838b8e) will increase coverage by 0.02%.
The diff coverage is 100.00%.

Additional details and impacted files

@@            Coverage Diff             @@
##           master   #11205      +/-   ##
==========================================
+ Coverage   61.23%   61.26%   +0.02%     
==========================================
  Files         839      839              
  Lines       51856    51877      +21     
  Branches     6655     6658       +3     
==========================================
+ Hits        31755    31783      +28     
+ Misses      18570    18563       -7     
  Partials     1531     1531