style: remove unused import

Author: Vinzent03

packages/supabase_flutter/lib/src/supabase.dart

@@ -1,6 +1,4 @@
 import 'dart:async';
-import 'dart:developer' as dev;
-import 'dart:io';
 
 import 'package:async/async.dart';
 import 'package:flutter/foundation.dart';