supabase-todolist Demo App - SupabaseConnector does not need a db instance

[JavascriptMick]

Pretty sure there is an unnecessary and, frankly confusing mistake in the supabase-todolist demo code.

e.g. this file....
https://github.com/powersync-ja/powersync.dart/blob/main/demos/supabase-todolist/lib/powersync.dart

From Line 28

class SupabaseConnector extends PowerSyncBackendConnector {
  PowerSyncDatabase db;

  Future<void>? _refreshFuture;

  SupabaseConnector(this.db);

the db instance is not used inside the class or by users of the class. Smells like a refactor happened and this was left in. I was able to rip the property out and run the demo app just fine...

class SupabaseConnector extends PowerSyncBackendConnector {
  Future<void>? _refreshFuture;

  SupabaseConnector();

[mugikhan]

Thanks for reporting this @JavascriptMick we've removed the unnecessary db instances in the connectors for all the demos.