Page provider resultsCount not correctly computed on mongodb

Steps to reproduce on nightly:

• add 2 documents to a collection
• Send a GET on https://nightly.nuxeo.com/nuxeo/api/v1/search/pp/ordered_content_collection/execute?currentPageIndex=0&pageSize=40&queryParams= {collectionUid}
• Observe the response:

  {
      "currentPageIndex": 0, 
      "currentPageOffset": 0, 
      "currentPageSize": 4, 
      "entity-type": "documents", 
      "entries": [
          ...
      ], 
      "errorMessage": null, 
      "hasError": false, 
      "isLastPageAvailable": false, 
      "isNextPageAvailable": false, 
      "isPaginable": true, 
      "isPreviousPageAvailable": false, 
      "isSortable": true, 
      "maxPageSize": 1000, 
      "numberOfPages": 1, 
      "pageCount": 1, 
      "pageIndex": 0, 
      "pageSize": 40, 
      "resultsCount": 1, 
      "resultsCountLimit": 0, 
      "totalSize": 1
  }
  

  see that "currentPageSize": 4 but "resultsCount": 1