Fix facet filter not applied

[shinyichen]

Fix bug where only first search filter is applied. The query doesn't work correctly when the format of the array fq param is comma, but works if format is repeat.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 47.3%. Comparing base (b46de25) to head (0c48a8d).
Report is 8 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff            @@
##           master    #496     +/-   ##
========================================
- Coverage    47.3%   47.3%   -0.0%     
========================================
  Files         427     427             
  Lines       44836   44846     +10     
  Branches      624     624             
========================================
- Hits        21197   21196      -1     
- Misses      23627   23638     +11     
  Partials       12      12             

Files	Coverage Δ
src/api/config.ts	69.3% <100.0%> (ø)
src/utils.ts	85.8% <100.0%> (ø)

... and 2 files with indirect coverage changes