deps: bump mongoid-scroll to 2.0

[markokajzer]

update mongoid-scroll as discussed here

[dangerpr-bot]

	1 Warning
⚠️	There're library changes, but not tests. That's OK as long as you're refactoring existing code.

Generated by 🚫 Danger

[dblock]

I think we have a flaky test here:

  1) Teams oauth v2 oauth includes optional parameter
     Failure/Error: expect(SlackRubyBotServer::Service.instance).to receive(:create!).with(instance_of(Team), { state: 'property' })

       (#<SlackRubyBotServer::Service:0x000055ee85737d90 @callbacks={"creating"=>[], "created"=>[], "starting"=>[], "started"=>[]}, @intervals={}>).create!(an_instance_of(Team), {:state=>"property"})
           expected: 1 time with arguments: (an_instance_of(Team), {:state=>"property"})
           received: 0 times
     # ./spec/integration/teams_spec.rb:61:in `block (4 levels) in <top (required)>'
     # ./spec/database_adapters/mongoid/database_cleaner.rb:11:in `block (3 levels) in <top (required)>'
     # ./spec/database_adapters/mongoid/database_cleaner.rb:10:in `block (2 levels) in <top (required)>'

Care to take a look?