[v0.108.0-b.58] Lots of errors: Client.Timeout exceeded while awaiting headers

### Prerequisites

- [X] I have checked the [Wiki](https://github.com/AdguardTeam/AdGuardHome/wiki) and [Discussions](https://github.com/AdguardTeam/AdGuardHome/discussions/categories/q-a) and found no answer

- [X] I have searched other issues and found no duplicates

- [X] I want to report a bug and not [ask a question or ask for help](https://github.com/AdguardTeam/AdGuardHome/discussions/categories/q-a)

- [X] I have set up AdGuard Home correctly and [configured clients to use it](https://github.com/AdguardTeam/AdGuardHome/wiki/Clients). (Use the [Discussions](https://github.com/AdguardTeam/AdGuardHome/discussions/categories/q-a) for help with installing and configuring clients.)

### Platform (OS and CPU architecture)

Linux, MIPS LE

### Installation

GitHub releases or script from README

### Setup

On a router, DHCP is handled by the router

### AdGuard Home version

v0.108.0-b.58

### Action

Lots of timeout errors that I believe started with

```
2024/10/12 06:34:00.268414 ERROR response received addr=https://dns.controld.com:443/... proto=udp status="requesting https://dns.controld.com:443/...: Get_0rtt \"https://dns.controld.com:443/...?dns=AAA...AAA\": context deadline exceeded (Client.Timeout exceeded while awaiting headers)"
```

The network is fine, ping times to controld are 7-8ms.

What should the `upstream_timeout` be set to? I changed it from the default 10s to 1s because 10s is way too much to wait for a DNS query, even 1s is a lot. Are these errors related to `upstream_timeout` and maybe 0-RTT issues in quic-go?

It seems to use HTTP/3, is there a way to force it to HTTP/2 only?

### Expected result

very few errors

### Actual result

lots of errors

### Additional information and/or screenshots

_No response_