Updated the container doc (#34682)

Author: liferoad

website/www/site/content/en/documentation/runtime/environments.md

@@ -19,7 +19,7 @@ limitations under the License.
 
 The Beam SDK runtime environment can be [containerized](https://www.docker.com/resources/what-container) with [Docker](https://www.docker.com/) to isolate it from other runtime systems. To learn more about the container environment, read the Beam [SDK Harness container contract](https://s.apache.org/beam-fn-api-container-contract).
 
-Prebuilt SDK container images are released per supported language during Beam releases and pushed to [Docker Hub](https://hub.docker.com/search?q=apache%2Fbeam&type=image).
+Prebuilt SDK container images are released per supported language during Beam releases and pushed to [Docker Hub](https://hub.docker.com/search?q=apache%2Fbeam&type=image). **Note:** These images, such as `apache/beam_python3.12_sdk:2.63.0`, are designed specifically as worker images for the distributed execution of Beam pipelines. They are not intended as fully featured SDK development environments.
 
 ## Custom containers