Fix method redefinition warnings

These are harmless but I'm trying to get my application warning free because warnings tend to
point nasty bugs.

```
lib/twilio-ruby/util/configuration.rb:8: warning: method redefined; discarding old account_sid=
lib/twilio-ruby/util/configuration.rb:12: warning: method redefined; discarding old auth_token=
lib/twilio-ruby/util/configuration.rb:16: warning: method redefined; discarding old http_client=
lib/twilio-ruby/util/configuration.rb:20: warning: method redefined; discarding old region=
lib/twilio-ruby/util/configuration.rb:24: warning: method redefined; discarding old edge=
lib/twilio-ruby/util/configuration.rb:28: warning: method redefined; discarding old logger=
```

There are a number of warnings left but I can't fix them because they are in generated code.

Almost all of them have to do witht the `context` method:

```
lib/twilio-ruby/rest/studio/v1/flow/engagement.rb:321: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v1/flow/engagement.rb:282: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v1/flow/engagement/engagement_context.rb:162: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v1/flow/engagement/engagement_context.rb:143: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v1/flow/engagement/step.rb:293: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v1/flow/engagement/step.rb:249: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v1/flow/engagement/step/step_context.rb:170: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v1/flow/engagement/step/step_context.rb:150: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v1/flow/execution.rb:367: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v1/flow/execution.rb:328: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v1/flow/execution/execution_context.rb:163: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v1/flow/execution/execution_context.rb:144: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v1/flow/execution/execution_step.rb:299: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v1/flow/execution/execution_step.rb:255: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v1/flow/execution/execution_step/execution_step_context.rb:173: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v1/flow/execution/execution_step/execution_step_context.rb:153: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v2/flow/execution.rb:360: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v2/flow/execution.rb:327: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v2/flow/execution/execution_context.rb:163: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v2/flow/execution/execution_context.rb:144: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v2/flow/execution/execution_step.rb:299: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v2/flow/execution/execution_step.rb:255: warning: previous definition of context was here
lib/twilio-ruby/rest/studio/v2/flow/execution/execution_step/execution_step_context.rb:173: warning: method redefined; discarding old context
lib/twilio-ruby/rest/studio/v2/flow/execution/execution_step/execution_step_context.rb:153: warning: previous definition of context was here
lib/twilio-ruby/twiml/voice_response.rb:794: warning: method redefined; discarding old initialize
lib/twilio-ruby/twiml/messaging_response.rb:50: warning: previous definition of initialize was here
```

lib/twilio-ruby/util/configuration.rb

@@ -3,7 +3,7 @@
 module Twilio
   module Util
     class Configuration
-      attr_accessor :account_sid, :auth_token, :http_client, :region, :edge, :logger
+      attr_reader :account_sid, :auth_token, :http_client, :region, :edge, :logger
 
       def account_sid=(value)
         @account_sid = value

spec/rack/twilio_webhook_authentication_spec.rb

@@ -37,7 +37,7 @@
       expect(Twilio::Security::RequestValidator).to receive(:new).with(auth_token).and_return(request_validator)
       expect(request_validator).to receive(:validate).and_return(true)
       request = Rack::MockRequest.env_for('/voice')
-      status, headers, body = @middleware.call(request)
+      status, _headers, _body = @middleware.call(request)
       expect(status).to be(200)
     end
   end
@@ -50,7 +50,7 @@
     it 'should not intercept when the path doesn\'t match' do
       expect(Twilio::Security::RequestValidator).to_not receive(:validate)
       request = Rack::MockRequest.env_for('/sms')
-      status, headers, body = @middleware.call(request)
+      status, _headers, _body = @middleware.call(request)
       expect(status).to be(200)
     end
 
@@ -59,7 +59,7 @@
         receive(:validate).and_return(true)
       )
       request = Rack::MockRequest.env_for('/voice')
-      status, headers, body = @middleware.call(request)
+      status, _headers, _body = @middleware.call(request)
       expect(status).to be(200)
     end
 
@@ -68,7 +68,7 @@
         receive(:validate).and_return(false)
       )
       request = Rack::MockRequest.env_for('/voice')
-      status, headers, body = @middleware.call(request)
+      status, _headers, _body = @middleware.call(request)
       expect(status).to be(403)
     end
   end
@@ -81,7 +81,7 @@
     it 'should not intercept when the path doesn\'t match' do
       expect(Twilio::Security::RequestValidator).to_not receive(:validate)
       request = Rack::MockRequest.env_for('icesms')
-      status, headers, body = @middleware.call(request)
+      status, _headers, _body = @middleware.call(request)
       expect(status).to be(200)
     end
 
@@ -90,7 +90,7 @@
         receive(:validate).and_return(true)
       )
       request = Rack::MockRequest.env_for('/sms')
-      status, headers, body = @middleware.call(request)
+      status, _headers, _body = @middleware.call(request)
       expect(status).to be(200)
     end
 
@@ -99,7 +99,7 @@
         receive(:validate).and_return(false)
       )
       request = Rack::MockRequest.env_for('/sms')
-      status, headers, body = @middleware.call(request)
+      status, _headers, _body = @middleware.call(request)
       expect(status).to be(403)
     end
   end

spec/spec_helper.rb

@@ -1,3 +1,5 @@
+$VERBOSE = true
+
 require 'simplecov'
 SimpleCov.start