Remove two unused fields. (#425)

Co-authored-by: Michael Richardson <mcr@sandelman.ca>

src/error.rs

@@ -94,7 +94,6 @@ pub struct Transport {
     message: Option<String>,
     url: Option<Url>,
     source: Option<Box<dyn error::Error + Send + Sync + 'static>>,
-    response: Option<Response>,
 }
 
 /// Extension to [`Result<Response, Error>`] for handling all status codes as [`Response`].
@@ -193,7 +192,6 @@ impl Error {
             message,
             url: None,
             source: None,
-            response: None,
         })
     }
 

src/request.rs

@@ -30,7 +30,6 @@ pub struct Request {
     agent: Agent,
     method: String,
     url: String,
-    error_on_non_2xx: bool,
     headers: Vec<Header>,
     timeout: Option<time::Duration>,
 }
@@ -52,7 +51,6 @@ impl Request {
             method,
             url,
             headers: vec![],
-            error_on_non_2xx: true,
             timeout: None,
         }
     }