fix: access violation on MS SQL connections, after applying filter on data tab

Refs #2599

Author: ansgarbecker

source/dbconnection.pas

@@ -8179,6 +8179,7 @@ procedure TSqlSrvQuery.Execute(AddResult: Boolean=False; UseRawResult: Integer=-
       FResultList[i].Close;
       FResultList[i].Free;
     end;
+    FResultList.Clear;
     NumResults := 1;
     FRecordCount := 0;
     FAutoIncrementColumn := -1;