Add a spec which demonstrates how args work with stub chain

spec/rspec/mocks/stub_chain_spec.rb

@@ -29,6 +29,13 @@ module Mocks
       end
 
       context "with two methods in chain" do
+        it "accepts any number of arguments to the stubbed messages in the chain" do
+          object.stub_chain(:msg1, :msg2).and_return(:return_value)
+          expect {
+            object.msg1("nonsense", :value).msg2("another", :nonsense, 3.0, "value")
+          }.not_to raise_error
+        end
+
         context "using and_return" do
           it "returns expected value from chaining two method calls" do
             object.stub_chain(:msg1, :msg2).and_return(:return_value)