User custom filter: CSS selector "has()" does not work

### Prerequisites

Please answer the following questions for yourself before submitting an issue. **YOU MAY DELETE THE PREREQUISITES SECTION.**

- [O] I am running the latest version
- [O] I checked the documentation and found no answer
- [O] I checked to make sure that this issue has not already been filed

### Issue Details

- **AdGuard version:**
- 2.6.0
- **Browser:**
- Samsung Internet
- **Device model:**
- Galaxy Note 10
- **Operating system and version:**
- Android 10

I am not sure this is a bug or a feature that is not yet adapted in the Adguard Content Blocker.
CSS selector ':has(selector)' and '[-ext-has="selector"]' do not work in Adguard Content Blocker.

Those filters are listed in the Adguard custom filter guidelines.
https://kb.adguard.com/en/general/how-to-create-your-own-ad-filters#extended-css-selectors-1

### Expected Behavior

1. Write own filter as follows:
google.com##div:has(img[alt="Google"])
2. Access google.
3. Nothing shows (tested in PC browser with uBlock)

### Actual Behavior

Filter with ":has()" selector is neglected.
I've tried ##, #$#, #?#, :has(), and [-ext-has] but none of them worked.