📝 add note about non-retrieable errors

Author: floatdrop

readme.md

@@ -120,6 +120,8 @@ Default: `5`
 
 Number of request retries when network errors happens. Delays between retries counts with function `Math.pow(2, retry) + Math.random() * 100`, where `retry` is attempt number (starts from 0).
 
+**Note:** `ENOTFOUND` and `ENETUNREACH` error will not be retried (see full list in [`is-retry-allowed`](https://github.com/floatdrop/is-retry-allowed/blob/master/index.js#L12) module).
+
 Option accepts `function` with `retry` and `error` arguments. Function must return delay in milliseconds (`0` return value cancels retry).