Remove unnecessary use statement

Resolves styleci issues of mongodb#1306

Author: Yahatix

src/Jenssegers/Mongodb/Query/Builder.php

@@ -10,7 +10,6 @@
 use Illuminate\Support\Collection;
 use Illuminate\Support\Str;
 use Jenssegers\Mongodb\Connection;
-use MongoCollection;
 use MongoDB\BSON\Binary;
 use MongoDB\BSON\ObjectID;
 use MongoDB\BSON\Regex;