Web: JS: Fix retrieve from WS to return existing Promise if exists

Since was not returning existing promise, was loading the data again for
each call while the retrieval was in progress.

Valid data was always shown.  This is a performance improvement.

limelight_webapp/front_end/src/js/page_js/data_pages/common_data_loaded_from_server__per_search_plus_some_assoc_common_data__with_loading_code__except_mod_main_page/common_data_loaded_from_server_single_search_sub_parts__returned_objects/commonData_LoadedFromServer_SingleSearch__ReportedPeptideId_Based_Data_For_MainFilters.ts

@@ -694,7 +694,7 @@ export class CommonData_LoadedFromServer_SingleSearch__ReportedPeptideId_Based_D
 
             //  Return already in progress Promise
 
-            this._load_Num_PSM_Data_From_Num_PSMs_Webservice__InProgressPromise; // EARLY RETURN
+            return this._load_Num_PSM_Data_From_Num_PSMs_Webservice__InProgressPromise; // EARLY RETURN
         }
 
         const promise_load = this._load_Num_PSM_Data_From_Num_PSMs_Webservice_Actual();