fix: do not retry 4xx status codes (#46)

Author: dsherret

file_fetcher.ts

@@ -328,7 +328,10 @@ export async function fetchWithRetries(
     iterationCount++;
     try {
       const res = await fetch(url, init);
-      if (res.ok || iterationCount > maxRetries) {
+      if (
+        res.ok || iterationCount > maxRetries ||
+        res.status >= 400 && res.status < 500
+      ) {
         return res;
       }
     } catch (err) {