Add changelog for 8.4.0 release

Author: Anaethelion

CHANGELOG.md

@@ -1,6 +1,30 @@
+# 8.4.0
+
+## API
+
+* `get`, `mget` and `search` added `force_synthetic_source`: Should this request force synthetic _source? Use this to test if the mapping supports synthetic _source and to get a sense of the worst case performance. Fetches with this enabled will be slower the enabling synthetic source natively in the index.
+* `ML.StartTrainedModelDeployment` added `cache_size`: A byte-size value for configuring the inference cache size. For example, 20mb.
+* `Snapshot.Get` added `sort`, `size`, `order`, `from_sort_value`, `after`, `offset` and `slm_policy_filter`. More on these in the [documentation](https://www.elastic.co/guide/en/elasticsearch/reference/8.4/get-snapshot-api.html).
+
+**New API**
+
+* `Security.UpdateAPIKey` [documentation](https://www.elastic.co/guide/en/elasticsearch/reference/8.4/security-api-update-api-key.html).
+
+## Typed API
+
+As highlighted in the release not for the 8.4.0-alpha.1, this release marks the beginning of the newly arrived `TypedClient`.
+
+This new API is still in `alpha` stage and will be release alongside the existing `esapi`.
+
+A few examples of standard use-cases can be found in the [TypedAPI section of the documentation](https://www.elastic.co/guide/en/elasticsearch/client/go-api/master/typedapi.html).
+
+# 8.4.0-alpha.2
+
+This second prerelease of the 8.4.0 updates the API for the client and fixes the serialization for types using [additional properties](https://github.com/elastic/elasticsearch-specification/blob/main/docs/behaviors.md#additionalproperties--additionalproperty).
+
 # 8.4.0-alpha.1
 
-This prerelease introduces a new typed API generated from the [elasticsearch-specification](https://github.com/elastic/elasticsearch-specification). This generation from the common specification allows us to provide a complete API which uses an exhaustive hierarchy of types  reflecting the possibilities given by Elasticsearch. 
+This prerelease introduces a new typed API generated from the [elasticsearch-specification](https://github.com/elastic/elasticsearch-specification). This generation from the common specification allows us to provide a complete API which uses an exhaustive hierarchy of types  reflecting the possibilities given by Elasticsearch.
 
 This new API is the next iteration of the Go client for Elasticsearch, it now lives alongside the existing API, it is in `alpha` state and will gain features over time and releases.
 
@@ -11,19 +35,19 @@ The `TypedClient` is built around a fluent builder for easier request creation a
 As a first example, here is a search request:
 ```go
 cfg := elasticsearch.Config{
-	// Define your configuration
+// Define your configuration
 }
 es, _ := elasticsearch.NewTypedClient(cfg)
 res, err := es.Search().
-    Index("index_name").
-    Request(&search.Request{
-        Query: &types.QueryContainer{
-            Match: map[types.Field]types.MatchQuery{
-                "name": {Query: "Foo"},
-            },
-        },
-    },
-    ).Do(context.Background())
+Index("index_name").
+Request(&search.Request{
+Query: &types.QueryContainer{
+Match: map[types.Field]types.MatchQuery{
+"name": {Query: "Foo"},
+},
+},
+},
+).Do(context.Background())
 ```
 
 The `Request` uses the structures found in the `typedapi/types` package which will lead you along the possibilities. A builder for each structure that allows easier access and declaration is also provided.
@@ -64,7 +88,7 @@ Feedback is very welcome, play with it, use it, let us know what you think!
 ## Client
 
 * Fixed a serialisation error for `retry_on_conflict` in the BulkIndexer. Thanks to @lpflpf for the help!
-* Fixed a concurrent map error in the BulkIndexer when custom headers are applied. Thanks to @chzhuo for the contribution! 
+* Fixed a concurrent map error in the BulkIndexer when custom headers are applied. Thanks to @chzhuo for the contribution!
 
 ## API
 
@@ -83,11 +107,11 @@ Feedback is very welcome, play with it, use it, let us know what you think!
 # 8.1.0
 ## API
 
- * API is generated from the Elasticsearch 8.1.0 specification.
+* API is generated from the Elasticsearch 8.1.0 specification.
 
 **New parameters**
 
-* `WithWaitForCompletion` for `Indices.Forcemerge` 
+* `WithWaitForCompletion` for `Indices.Forcemerge`
 * `WithFeatures` for `Indices.Get`
 * `WithForce` for `ML.DeleteTrainedModel`
 
@@ -99,14 +123,14 @@ Feedback is very welcome, play with it, use it, let us know what you think!
 # 8.0.0
 ## Client
 
- * The client now uses `elastic-transport-go` dependency which lives in its [own repository](https://github.com/elastic/elastic-transport-go/).
- * With the knewly extracted transport, the `retryOnTimeout` has been replaced with a `retryOnError` callback. This allows to select more finely which error should be retried by the client.
- * `BulkIndexerItem` `Body` field is now an `io.ReadSeeker` allowing reread without increasing memory consumption.
- * `BulkIndexerItem` know correctly uses the `routing` property instead of the deprecated `_routing`.
+* The client now uses `elastic-transport-go` dependency which lives in its [own repository](https://github.com/elastic/elastic-transport-go/).
+* With the knewly extracted transport, the `retryOnTimeout` has been replaced with a `retryOnError` callback. This allows to select more finely which error should be retried by the client.
+* `BulkIndexerItem` `Body` field is now an `io.ReadSeeker` allowing reread without increasing memory consumption.
+* `BulkIndexerItem` know correctly uses the `routing` property instead of the deprecated `_routing`.
 
 ## API
 
- * API is generated from the Elasticsearch 8.0.0 specification.
+* API is generated from the Elasticsearch 8.0.0 specification.