Save the actual Github API response body for uri to a file

Property definitions

github $ MockGithubAPI :: save_actual_response
	# Save the actual Github API response body for `uri` to a `file`
	private fun save_actual_response(uri, file: String) do
		assert update_responses_cache

		var request = new CurlHTTPRequest("{api_url}{sanitize_uri(uri)}")
		request.user_agent = actual_api.user_agent
		request.headers = actual_api.new_headers
		var response = request.execute

		if response isa CurlResponseSuccess then
			response.body_str.write_to_file(file)
		else if response isa CurlResponseFailed then
			response.error_msg.write_to_file(file)
		else abort

		print "Response to `{uri}` saved at `{file}`"
	end
lib/github/tests/test_api.nit:135,2--151,4