Make `id` field required for CosmosDB v4 output binding

[hossam-nasr]

In v3.x of the CosmosDB extension, an id field was not required for CosmosDB output bindings, as an autogenerated GUID was assigned if no id was explicitly specified. One less documented change in v4.x is that now an id field is required, and an ID field is no longer automatically generated if none is specified. This is related to a similar change on the underlying SDK. We recently had a CRI where a customer (using a node app) was confused about this new behavior, especially since it is not well documented. We can help mitigate future confusion by making an id field required when setting a CosmosDB v4 output binding.