Track bugfix for httpclient.safeCurl typing
This issue is created to track the bugfix for the httpclient.safeCurl typing. The related pull request is [#5341](https://github.com/eggjs/egg/pull/5341). The bugfix will be merged into the master branch as per [fengmk2's comment](https://github.com/eggjs/egg/pull/5341#issuecomment-1634567890).