Generated tests should not suggest read-only in request

[lmazuel]

See this field that is visibility("read"):
https://github.com/Azure/azure-rest-api-specs/blob/c9a4dc04527f7fdb4a944e2c392f2de280ef7cae/specification/durabletask/DurableTask.Management/main.tsp#L70

And the generated test for Python looks like this:

@recorded_by_proxy
    def test_schedulers_begin_update(self, resource_group):
        response = self.client.schedulers.begin_update(
            resource_group_name=resource_group.name,
            scheduler_name="str",
            properties={
                "location": "str",
                "id": "str",
                "name": "str",
                "properties": {
                    "ipAllowlist": ["str"],
                    "sku": {"name": "str", "capacity": 0, "redundancyState": "str"},
                    "endpoint": "str",
                    "provisioningState": "str",
                },
                "systemData": {
                    "createdAt": "2020-02-20 00:00:00",
                    "createdBy": "str",
                    "createdByType": "str",
                    "lastModifiedAt": "2020-02-20 00:00:00",
                    "lastModifiedBy": "str",
                    "lastModifiedByType": "str",
                },
                "tags": {"str": "str"},
                "type": "str",
            },
        ).result()  # call '.result()' to poll until service return final result

Note that we suggest redundancyState in the request. As this field is "read", it should not be suggested and should be ommmited.