[Bug]: Changes in synchronized folders could not be tracked reliably.

### ⚠️ Before submitting, please verify the following: ⚠️

- [x] This is a **bug**, not a question or a configuration issue.
- [x] This issue is **not** already reported on Github (I've searched it).
- [x] Nextcloud Server and Desktop Client are **up to date**. See [Server Maintenance and Release Schedule](https://github.com/nextcloud/server/wiki/Maintenance-and-Release-Schedule) and [Desktop Releases](https://nextcloud.com/install/#install-clients) for supported versions.
- [x] I agree to follow Nextcloud's [Code of Conduct](https://nextcloud.com/contribute/code-of-conduct/)

### Bug description

When starting nextcloud client (on a Debian sid system running KDE Plasma), I get the following warning / notification:
```
Changes in synchronized folders could not be tracked reliably.
This means that the synchronization client might not upload local changes immediately and will instead only scan for local changes and upload them occasionally (every two hours by default).
The watcher did not receive a test notification.
```

### Steps to reproduce

Start nextcloud client, wait for a few seconds to have this notification pop up.

### Expected behavior

No such error or at least provide instructions how to fix them.

I did find https://help.nextcloud.com/t/fedora-30-client-message-changes-in-synchronized-folders-could-not-be-tracked-reliably/57228

```
$ cat /proc/sys/fs/inotify/max_user_watches
65536
```
I tried increasing that value:
```
sudo echo 6553600 > /proc/sys/fs/inotify/max_user_watches
```
but that didn't help.

### Which files are affected by this bug

can't say

### Operating system

Linux

### Which version of the operating system you are running.

Debian sid

### Package

Distro package manager

### Nextcloud Server version

30.0.5

### Nextcloud Desktop Client version

3.15.2-2

### Is this bug present after an update or on a fresh install?

Fresh desktop client install

### Are you using the Nextcloud Server Encryption module?

Encryption is Disabled

### Are you using an external user-backend?

- [ ] Default internal user-backend
- [ ] LDAP/ Active Directory
- [ ] SSO - SAML
- [ ] Other

### Nextcloud Server logs

```shell

```

### Additional info

_No response_