Processor mismatched on Lenovo ThinkPad X1 Carbon Gen 13

### Check existing issues

- [x] I've verified that this bug isn't described by any existing issues.

### Bug description

`certified_url` shows the same model but different processor.
- certified_url: Intel Corp. Intel(R) Core(TM) Ultra 7 258V
- on the machine: Intel(R) Core(TM) Ultra 7 268V

```
> hwctl
{
"status": "Certified",
"certified_url": "https://ubuntu.com/certified/202411-36001",
"available_releases": [
{
"codename": "noble",
"distributor": "Ubuntu",
"version": "24.04",
"kernel": {
"name": null,
"version": "6.11.0-1020-oem",
"signature": null,
"loaded_modules": []
}
}
],
"valid_cache": true,
"hardware_mismatch": false,
"stale": false,
"stale_reason": null,
"source": "server",
"remote_access_enabled": false,
"server_url": "https://hw.ubuntu.com"
}%
```

### Environment

- OS: 24.04
- hwctl type: snap
- hwctl version: hwlib 0.11.1
- Hardware model from dmidecode
- Version: ThinkPad X1 Carbon Gen 13
- SKU Number: LENOVO_MT_21NS_BU_Think_FM_ThinkPad X1 Carbon Gen 13
- Family: ThinkPad X1 Carbon Gen 13

### Relevant log output

```shell
"processor": {
"identifier": [
209,
6,
11,
0,
255,
251,
235,
191
],
"frequency": 5000,
"manufacturer": "Intel(R) Corporation",
"version": "Intel(R) Core(TM) Ultra 7 268V"
},
"usb_peripherals": [],
"vendor": "LENOVO"
}
```

### Additional context

_No response_

No source file or test is named. Start by reproducing the hwctl output on the reported ThinkPad and trace the certified_url lookup through the server_url; compare the returned processor with the dmidecode and log values. Done means the certification result correctly handles the 258V versus 268V processor distinction.

Written by the indexing model from the issue text.