Apply suggestions from code review

test/req/steps_test.exs

@@ -293,8 +293,8 @@ defmodule Req.StepsTest do
     end)
 
     response = Req.get!(c.url)
-
-    assert content_length(response) == byte_size(body)
+    [content_length] = Req.Response.get_header(response, "content-length")
+    assert String.to_integer(content_length) == byte_size(body)
   end
 
   @tag :tmp_dir
@@ -1385,12 +1385,4 @@ defmodule Req.StepsTest do
 
     Plug.Conn.send_resp(conn, status, Jason.encode_to_iodata!(data))
   end
-
-  defp content_length(response) do
-    {"content-length", content_length_str} = List.keyfind!(response.headers, "content-length", 0)
-
-    {content_length, _remainder} = Integer.parse(content_length_str)
-
-    content_length
-  end
 end