Some requests in the cache are slow

### Prerequisites

- [X] I have checked the [Wiki](https://github.com/AdguardTeam/AdGuardHome/wiki) and [Discussions](https://github.com/AdguardTeam/AdGuardHome/discussions) 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

### Operating system type

Linux, Other (please mention the version in the description)

### CPU architecture

ARMv7

### Installation

Docker

### Setup

On one machine

### AdGuard Home version

v0.108.0-b.23

### Description

#### What did you do?
I notice that sometimes DNS lookup in the cache are slow. Usually they take around 1-3ms but frequently they are around 30-40 ms and more rarely 100ms. There’s no way to analyze more in detail the behavior of the cache.

#### Expected result
DNS lookup in the cache are more constantly around a couple of ms.

#### Actual result

#### Screenshots (if applicable)

#### Additional information
AdguardHome is installed on a NAS via docker.