[BUG] PutPipelineRequest not deserializable due to missing `id` field

[patschl]

What is the bug?

Currently PutPipelineRequests cannot be deserialized due to the id field not being set.

How can one reproduce the bug?

Create a PutPipelineRequest and add an id to the json, then use PutPipelineRequest._DESERIALIZER to deserialize the json.

What is the expected behavior?

Creates a valid PutPipelineRequest.

What is your host/environment?

Managed AWS OpenSearch/local docker container.