fix(http): fix 'socket hang up' bug for keep-alive requests when using timeouts; (#7206)

lib/adapters/http.js

@@ -858,6 +858,9 @@ export default isHttpAdapterSupported && function httpAdapter(config) {
           req
         ));
       });
+    } else {
+      // explicitly reset the socket timeout value for a possible `keep-alive` request
+      req.setTimeout(0);
     }