Change the get data stream api to include the following properties of a data stream:

- ~~Add `index_mode` from `DataStream` to the response.~~
- For each backing index of a data stream with time series index mode, include the temporal range the backing index represents (based on the `index.time_series.start_time` and `index.time_series.end_time` index settings.
server/src/main/java/org/elasticsearch/action/datastreams/GetDataStreamAction.java
}
        @Override
        public void writeTo(StreamOutput out) throws IOException {
            out.writeList(dataStreams);
        }
        @Override
        public XContentBuilder toXContent(XContentBuilder builder, Params params) throws IOException {
            builder.startObject();
            builder.startArray(DATASTREAMS_FIELD.getPreferredName());
            for (DataStreamInfo dataStream : dataStreams) {
                dataStream.toXContent(builder, params);
            }
            builder.endArray();
            builder.endObject();
            return builder;
        }
        @Override
        public boolean equals(Object o) {
            if (this == o) return true;
            if (o == null || getClass() != o.getClass()) return false;
            Response response = (Response) o;
            return dataStreams.equals(response.dataStreams);
        }
        @Override
        public int hashCode() {
            return Objects.hash(dataStreams);
        }
    }
}