How to preserve custom headers case in ruby 2.6.5

I am able to access api when try wit curl cmd, but same not able to access with net/http,

I did the string patch as per this link Preserving case in HTTP headers with Ruby's Net:HTTP and it was working well with ruby 2.2.4,

but recently we migrated to ruby 2.6.5 version, since then we are facing this issue again.

can anyone could help me with it.

sample code

token = JSON.parse(token_id)
  request = Net::HTTP::Get.new(uri)
  sso_token = token["headers"][0]["value"][0]
  request[CaseSensitiveString.new('sso_token')] = sso_token
  request["Accept"] = "application/json"
  req_options = {
      use_ssl: uri.scheme == "https"
  }
  response = Net::HTTP.start(uri.hostname, uri.port, req_options) do |http|
    http.request(request)
  end
  response.code
  response.body

class CaseSensitiveString < String
def downcase
  self
end
def capitalize
  self
end

end

Sorry, I needed to patch net/http as we have large existing project and its working with below code for ruby 2.5 and above

module Net::HTTPHeader 
    def capitalize(name)
     name 
    end 
    private :capitalize 
end