Update intune-enrollment-windowsautopilotdeviceidentity-list.md

Usability guidance for an expected API use-case.

API method does not currently support simple filter operators, but it does support the more complicated functional filters, which is likely to be counter-intuitive on average.

Author: Notheisz57

api-reference/v1.0/api/intune-enrollment-windowsautopilotdeviceidentity-list.md

@@ -36,6 +36,21 @@ One of the following permissions is required to call this API. To learn more, in
 GET /deviceManagement/windowsAutopilotDeviceIdentities
 ```
 
+## Optional query parameters
+This method supports certain [OData Query Parameters](/graph/query-parameters) to help customize the response.
+
+### Using filters
+This method supports a limited subset of `$filter` _operators_ and _functions_.  
+Most notably, Equality _operators_ such as `eq` are not currently supported.  
+
+Filter _functions_ can be used in-place of Equality _operators_, for example, `contains(serialNumber, '[DeviceSN]')`.
+
+Using an unsupported filter _operator_ or _function_ can result in the following error:
+
+- Error code: `BadRequest`
+- Error message: `An error has occurred - Operation ID (for customer support): 00000000-0000-0000-0000-000000000000 [...]`
+
+
 ## Request headers
 |Header|Value|
 |:---|:---|