Update domain restrictions for a playback ID
This endpoint updates domain-level restrictions for a specific playback ID associated with a media asset.
It allows you to restrict playback to specific domains or block known unauthorized domains.
**How it works:**
1. Make a `PATCH` request to this endpoint with your desired domain access configuration.
2. Set a default policy (`allow` or `deny`) and specify domain names in the `allow` or `deny` lists.
3. This is commonly used to restrict video playback to your website or approved client domains.
**Example:**
A streaming service can allow playback only from `example.com` and deny all others by setting: `"defaultPolicy": "deny"` and `"allow": ["example.com"]`.