Support generating an empty param option with polymorphism object without parameters

[calvinhzy]

https://github.com/calvinhzy/azure-rest-api-specs/blob/b0b51026d94ecc2f9748df05451fc5417bd974c4/specification/recoveryservicessiterecovery/resource-manager/Microsoft.RecoveryServices/stable/2022-08-01/service.json#L12880-L12895

2022-08-01 /subscriptions/{}/resourcegroups/{}/providers/microsoft.recoveryservices/vaults/{}/replicationfabrics/{}/replicationprotectioncontainers/{}/replicationprotectioncontainermappings/{}