Frontend "npx webpack --watch" only reflected on localhost but not 127.0.0.1

**Describe the bug**
On local development, Django starts on 127.0.0.1:8080, however `npx webpack --watch` only respects localhost:8080

**To Reproduce**
Steps to reproduce the behavior:
1. Load Label Studio locally `python3 label_studio/manage.py runserver`, Label Studio will be served on 127.0.0.1:8080
2. Go to the frontend directory and run `npx webpack --watch`
3. Changes in React code will not be reflected until you open label Studio on localhost:8080

**Expected behavior**
Changes should be also visible on 127.0.0.1:8080

**Environment (please complete the following information):**
- OS: Mac OS Big Sur
- Label Studio Version: 1.0