Add ranking_score_threshold parameter to search

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 100.00%. Comparing base (33f11c4) to head (bef8342).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## meilisearch-1.9.0 #955 +/- ## =================================================== Coverage 100.00% 100.00% =================================================== Files 19 19 Lines 2839 2857 +18 =================================================== + Hits 2839 2857 +18 ```

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