Can't add localhost to the allowlist

### Please answer the following questions for yourself before submitting an issue

- [x] Filters were updated before reproducing an issue
- [x] I checked the [knowledge base](https://adguard.com/kb/) and found no answer
- [x] I checked to make sure that this issue has not already been filed

### AdGuard Extension version

5.4.3.105

### Browser version

Chrome

### OS version

Windows 11

### Ad Blocking

AdGuard Base filter

### Privacy

AdGuard Tracking Protection filter

### Social

AdGuard Social Media filter

### Annoyances

AdGuard Cookie Notices filter

### Security

Online Malicious URL Blocklist

### Other

_No response_

### Language-specific

_No response_

### What Tracking protection options do you have enabled?

Block trackers

### Issue Details

Steps to reproduce:
1. Connect to a localhost dev server

### Expected Behavior

The dev server should work.

### Actual Behavior

AdGuard is blocking some assets:

If I try to add "localhost" or "localhost:3001" to my allowlist, the UI appears to save this; however, if I reload the page, the new entry is gone.

### Screenshots

Screenshot 1

### Additional Information

_No response_