Add hash value to spec to support ruby < 3.1

Author: mrj

spec/oauth2/access_token_spec.rb

@@ -422,8 +422,8 @@ def assert_initialized_token(target)
           end
         end
 
-        let(:options) { {mode:} }
-
+        let(:options) { {mode: mode} }
+        
         VERBS.each do |verb|
           it "correctly handles a #{verb.to_s.upcase}" do
             expect(subject.__send__(verb, "/token/#{mode.call(verb)}").body).to include(token)