Merge pull request #2270 from rspec/fix-deprecation-warning-in-have_broadcasted_to-matcher

Fix Ruby 2.7 deprecation in have_broadcasted_to

Author: pirj

lib/rspec/rails/matchers/action_cable/have_broadcasted_to.rb

@@ -13,10 +13,10 @@ def initialize(target, channel:)
             set_expected_number(:exactly, 1)
           end
 
-          def with(data = nil)
+          def with(data = nil, &block)
             @data = data
             @data = @data.with_indifferent_access if @data.is_a?(Hash)
-            @block = Proc.new if block_given?
+            @block = block if block
             self
           end