message: refactor(service-worker): remove redundant cache operation
  At this point, the response will have been cached (or scheduled to be
  cached) in other code paths, so caching it again is redundant.
  PR Close
diff: @@ -395,9 +395,7 @@ export class DataGroup {
  }
  // No response in the cache. No choice but to fall back on the full network fetch.
  - res = await networkFetch;
  - await this.cacheResponse(req, res, lru, true);
  - return res;
  + return networkFetch;
  }
  private networkFetchWithTimeout(req: Request): [Promise<Response|undefined>, Promise<Response>] {
  