Segfault on startup since update to qt-6.11.2

### ⚠️ 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 have searched for 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

Hi,

I have searched for duplicate issues and I think I haven't found any other report about this but I'm not 100% sure not to be wrong on this. Now to the bug:

Ever since I updated to qt-6.11.2 on my Gentoo Linux box, I can no longer successfully start nextcloud. It simply crashes with a segfault:

```
> gdb nextcloud
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This GDB was configured as "x86_64-pc-linux-gnu".
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Reading symbols from nextcloud...
(gdb) run
Starting program: /usr/bin/nextcloud
[New LWP 5710]
[New LWP 5711]
[New LWP 5712]
[New LWP 5713]
[New LWP 5714]
[New LWP 5715]
[New LWP 5716]
[New LWP 5717]
[New LWP 5718]
[New LWP 5719]
[New LWP 5720]

Thread 1 "nextcloud" received signal SIGSEGV, Segmentation fault.
0x00005555557a14c0 in QArrayDataPointer::needsDetach (this=0x0) at /usr/include/qt6/QtCore/qarraydatapointer.h:355
355 bool needsDetach() const noexcept { return !d || d->needsDetach(); }
(gdb) bt full
#0 0x00005555557a14c0 in QArrayDataPointer::needsDetach (this=0x0) at /usr/include/qt6/QtCore/qarraydatapointer.h:355
No locals.
#1 0x000055555579f967 in QtPrivate::QMovableArrayOps::emplace (this=0x7fffffffc9e0, i=0) at /usr/include/qt6/QtCore/qarraydataops.h:772
detach = 93
tmp = {d = {static MaxInternalSize = 24, data = {data = "\000\000\000\000\000\000\000\000\240ԆVUU\000\000\340\374\000\350\377\177\000", shared = 0x0, _forAlignment = 0}, is_shared = 0, is_null = 0, packedType = 35184372085448}}
growsAtBegin = 86
pos = (QArrayData::GrowsAtBeginning | unknown: 0x5554)
#2 0x00007ffff6ccd89e in ?? ()
No symbol table info available.
#3 0x00007fffffffcb60 in ?? ()
No symbol table info available.
#4 0x0000000000000000 in ?? ()
No symbol table info available.
(gdb)
```

I hope I don't need to recompile qt with debug symbols in order to provide useful information.

### Steps to reproduce

1. update to qt-6.11.2
2. run nextcloud desktop client
3. Observe segfault

### Expected behavior

Running desktop client.

### Which files are affected by this bug

/usr/include/qt6/QtCore/qarraydataops.h

### Operating system

Linux

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

Gentoo (rolling releases)

### Installation method

Distro package manager (please test with the AppImage package ?)

### Nextcloud Server version

32.0.14

### Nextcloud Desktop Client version

34.0.3

### Did this occur after an update or on a clean installation?

Minor version update (i.e. 33.0.0 → 33.0.1)

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

No

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

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

### Nextcloud Server logs

```shell

```

### Additional info

_No response_

Reproduce the startup crash on Gentoo after updating to qt-6.11.2 by running the desktop client under gdb. Start with the backtrace at /usr/include/qt6/QtCore/qarraydataops.h:355 and determine the affected client code; done means the client starts without a segmentation fault.

Written by the indexing model from the issue text.