Remove async-io dependency.

Author: ioquatix

async-rspec.gemspec

@@ -22,7 +22,6 @@ Gem::Specification.new do |spec|
 	spec.add_dependency "rspec-memory", "~> 1.0"
 
 	spec.add_development_dependency "async"
-	spec.add_development_dependency "async-io"
 	spec.add_development_dependency "bundler"
 	spec.add_development_dependency "covered"
 end

spec/async/rspec/reactor_spec.rb

@@ -5,7 +5,6 @@
 # Copyright, 2023, by Robin Goos.
 
 require 'async/rspec/reactor'
-require 'async/io/generic'
 
 RSpec.describe Async::RSpec::Reactor do
 	context "with shared context", timeout: 1 do