Adding Encryption Certificate Crashes Adguard Service, and it no longer runs unless reinstalled

### 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, ARMv7

### Installation

Custom package (OpenWrt, HomeAssistant, etc; please mention in the description)

### Setup

On one machine

### AdGuard Home version

v0.107.63

### Action

Copied Certificate and Private Key content on the Encryption Tab.

### Expected result

After pressing "Save", the encryption certificate is saved.

### Actual result

The Adguard service crashes.

Running `sudo /opt/AdGuardHome/AdGuardHome -s status` shows:
```
[info] AdGuard Home, version v0.107.63
[info] service: control action: status
[info] service: restarting after failed start
[info] service: action status has been done successfully on linux-systemd
```

### Additional information and/or screenshots

Using `hb-config` to install Adguard.

Same adguard configuration is working successfully on another machine running Linux ARM v6.

Tried to troubleshoot and service crash occurs only on the Encryption page after adding certificate contents. Certificate and private key are shown as valid, and crash occurs after hitting "Save".