Freeze a few more string constants
Freeze a few more string constants

Added .freeze to CODE_NAME, ERROR_400_RESPONSE, and ERROR_500_RESPONSE, I didn't see a reason why they weren't frozen
kyledrake/puma,wallclockbuilder/puma,nathansamson/puma,puma/puma,unleashed/puma,zapnap/puma,looker/puma,eileencodes/puma,ngpestelos/puma,nathansamson/puma,looker/puma,BenV/puma,kyledrake/puma,jbmyid/puma,puma/puma,ngpestelos/puma,respire/puma,zBMNForks/puma,prathamesh-sonpatki/puma,eileencodes/puma,ngpestelos/puma,nathansamson/puma,zBMNForks/puma,wallclockbuilder/puma,jc00ke/puma,arturocadena/puma,zBMNForks/puma,zapnap/puma,prathamesh-sonpatki/puma,snow/puma,jc00ke/puma,arturocadena/puma,jc00ke/puma,ngpestelos/puma,respire/puma,matthewd/puma,nathansamson/puma,BenV/puma,unleashed/puma,tuvistavie/puma,costi/puma,snow/puma,jbmyid/puma,snow/puma,BenV/puma,tuvistavie/puma,wallclockbuilder/puma,respire/puma,tuvistavie/puma,tuvistavie/puma,kyledrake/puma,puma/puma,snow/puma,costi/puma,eileencodes/puma,looker/puma,matthewd/puma,wallclockbuilder/puma,costi/puma,jc00ke/puma,kyledrake/puma,costi/puma,unleashed/puma,matthewd/puma,zBMNForks/puma,jbmyid/puma,matthewd/puma,arturocadena/puma,unleashed/puma,arturocadena/puma,eileencodes/puma,looker/puma,prathamesh-sonpatki/puma,prathamesh-sonpatki/puma,zapnap/puma,BenV/puma,respire/puma,jbmyid/puma,puma/puma,zapnap/puma