feat(execution_layer): log more detail when JWT auth fails (#9051)

Co-Authored-By: CATS <dev@yaksha3.ai>

Co-Authored-By: chonghe <44791194+chong-he@users.noreply.github.com>

beacon_node/execution_layer/src/engine_api.rs

@@ -79,7 +79,7 @@ impl From<reqwest::Error> for Error {
             e.status(),
             Some(StatusCode::UNAUTHORIZED) | Some(StatusCode::FORBIDDEN)
         ) {
-            Error::Auth(auth::Error::InvalidToken)
+            Error::Auth(auth::Error::InvalidToken(e.to_string()))
         } else {
             Error::HttpClient(e.into())
         }

beacon_node/execution_layer/src/engine_api/auth.rs

@@ -14,7 +14,7 @@ pub const JWT_SECRET_LENGTH: usize = 32;
 #[derive(Debug)]
 pub enum Error {
     JWT(jsonwebtoken::errors::Error),
-    InvalidToken,
+    InvalidToken(String),
     InvalidKey(String),
 }