Update deployment_id in ML trained model deployment start request (#2325) (#2335)

This adds the missing `deployment_id` query parameter to the `_start` request, that was introduced in v8.8.0.

[Docs](https://www.elastic.co/guide/en/elasticsearch/reference/8.8/start-trained-model-deployment.html#start-trained-model-deployment-query-params) say:

Author: github-actions[bot]

output/schema/schema.json

@@ -47,6 +47,11 @@ export interface Request extends RequestBase {
      * `0b` can be provided.
      */
     cache_size?: ByteSize
+    /**
+     * A unique identifier for the deployment of the model.
+     * @availability stack since=8.8.0
+     */
+    deployment_id?: string
     /**
      * The number of model allocations on each node where the model is deployed.
      * All allocations on a node share the same copy of the model in memory but use