Already existing domains are duplicated instead of rewriting after the exclusions' import

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

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

### AdGuard VPN version

Current version: 2.9.0 nightly 31 (2037)

### Environment

```markdown
- OS:
- Other network-level software:
```

### Which DNS server do you use?

Default

### Custom DNS

_No response_

### Use Wintun

- [ ] yes, I do

### Issue Details

Импортировать существующие домены.

### Expected Behavior

_No response_

### Actual Behavior

Программа перестала не импортировать существующие домены:

### Screenshots

Screenshot 1

### Additional Information

_No response_