[BUG] Microsoft.Web - Certificates_CreateOrUpdate operation is not marked as LRO

### API Spec link

https://github.com/Azure/azure-rest-api-specs/blob/main/specification/web/resource-manager/Microsoft.Web/AppService/stable/2023-12-01/Certificates.json#L160

### API Spec version

2023-12-01

### Describe the bug

The `Certificates_CreateOrUpdate` operation returns a 202 and is async but not marked as such in the API spec. (issue still present in [latest stable version](https://github.com/Azure/azure-rest-api-specs/blob/main/specification/web/resource-manager/Microsoft.Web/AppService/stable/2025-05-01/openapi.json#L2465) as well)

### Expected behavior

API spec is accurate

### Actual behavior

Inaccurate API spec

### Reproduction Steps

Create / Update a certificate
```
https://management.azure.com/subscriptions/{subscriptionID}/resourceGroups/{resourceGroupName}/providers/Microsoft.Web/certificates/{domain}?api-version=2023-12-01

{
"location": "westeurope",
"properties": {
"canonicalName": "{domain}",
"password": "",
"serverFarmId": "/subscriptions/{subscriptionID}/resourceGroups/{resourceGroupName}/providers/Microsoft.Web/serverfarms/{name}"
},
"tags": {}
}
```

See response:

```
:status: 202
...
location: https://management.azure.com/subscriptions/...Omitted for brevity... // async operation polling url
retry-after: 15
...
date: Mon, 16 Mar 2026 20:37:42 GMT
content-length: 0
```

### Environment

Terraform

Start with specification/web/resource-manager/Microsoft.Web/AppService/stable/2023-12-01/Certificates.json around line 160 and compare the operation with the latest stable specification linked in the issue. Verify how asynchronous 202 responses and polling metadata are represented for comparable operations; done means the certificate create/update operation is accurately marked as an LRO.

Written by the indexing model from the issue text.