Purview example Accounts_CreateOrUpdate.json is incorrect

The request payload of `specification/purview/resource-manager/Microsoft.Purview/stable/2021-07-01/examples/Accounts_CreateOrUpdate.json` seems to be incorrect because it doesn't include the `identity` parameter. Resource creation fails without it.

The schema confirms this. `purview.json` has `identity` as part of `TrackedResource`, and `Account` has `TrackedResource` included:
```
"allOf": [
{
"$ref": "#/definitions/TrackedResource"
}
],
```

Open specification/purview/resource-manager/Microsoft.Purview/stable/2021-07-01/examples/Accounts_CreateOrUpdate.json and compare its request payload with the identity definition in purview.json. Done means the example includes the required identity parameter and represents a request that can create the resource successfully.

Written by the indexing model from the issue text.