Deprecated cloud-init entries might be possible to remove some day

### Description

We still get some warnings, about the deprecated cloud-config syntax.

Like when running `cloud-init status --long` (for other reasons):

```
errors: []
recoverable_errors:
DEPRECATED:
- Deprecated cloud-config provided: users.0.ssh-authorized-keys: Deprecated in version 18.3. Use **ssh_authorized_keys** instead., users.0.uid: Changed in version 22.3. The use of ``string`` type is deprecated. Use an ``integer`` instead.
- Deprecated cloud-config provided: users.0.ssh-authorized-keys: Deprecated in version 18.3. Use **ssh_authorized_keys** instead., users.0.uid: Changed in version 22.3. The use of ``string`` type is deprecated. Use an ``integer`` instead.
```

It had compatibility issues, but some day it should be changed...

* [ ] ssh-authorized-keys -> ssh_authorized_keys - cloud-init 18.3

* [ ] uid (string) -> uid (integer) - cloud-init 22.3

Currently using cloud-init version 26.1, for the default template.

* https://github.com/lima-vm/lima/issues/3811

* https://github.com/lima-vm/lima/issues/2265

Start by locating the default cloud-config template that produces the users.0.ssh-authorized-keys and users.0.uid entries. Read the related Lima issues 3811 and 2265, then check the generated configuration against cloud-init 26.1. Done means the deprecated entries are addressed without breaking the compatibility cases described in those issues.

Written by the indexing model from the issue text.