automation software-update-configuration --included-update-classifications multi choices not support

- If the issue is to do with Azure CLI 2.0 in-particular, create an issue here at [Azure/azure-cli](https://github.com/Azure/azure-cli/issues)

### Related command

```
az automation software-update-configuration create --automation-account-name automation-p1beta \
--configuration-name devsl_test_2 \
--frequency OneTime \
--interval 0 \
--operating-system Windows \
--resource-group automation-p1beta \
--included-update-classifications "Critical,Security" \
--azure-virtual-machines "xxxx" \
--reboot-setting Never \
--start-time "2023-01-30T18:08:00+08:00"

```

### Extension name (the extension in question)

automation
### Description of issue (in as much detail as possible)

-----
Hi , teams
I am trying to do a windows virtual machine "windows update" with the automation account feature.
It is fine on the portal and we can choose multiple "included-update-classifications" , for ex: "Critical,Security".

But when we execute the az cli command to do so,
It seems like we can not select multi values for this args.
If we execute the command which I paste in this thread, it will throw
```
az automation software-update-configuration create: 'Critical,Security' is not a valid value for '--included-update-classifications'. Allowed values: Unclassified, Critical, Security, UpdateRollup, FeaturePack, ServicePack, Definition, Tools, Updates.
```

but in th [doc](https://learn.microsoft.com/en-us/cli/azure/automation/software-update-configuration?view=azure-cli-latest#az-
automation-software-update-configuration-create)
```
--included-update-classifications

Update classification included in the software update configuration. A comma separated string with required values.
accepted values: Critical, Definition, FeaturePack, Security, ServicePack, Tools, Unclassified, UpdateRollup, Updates
```

it said we can use the comma separated string as the multi-choice.

Need you support on this :
How could we select multi classifications in the az cli command line?