[CSM O11y] Follow-up from #36806 (#36823)

Closes #36823

COPYBARA_INTEGRATE_REVIEW=https://github.com/grpc/grpc/pull/36823 from yashykt:CsmObsEgFollowup b5d0dcd455
PiperOrigin-RevId: 640632444

examples/cpp/csm/observability/Dockerfile.client

@@ -34,6 +34,4 @@ RUN apt-get update \
 
 COPY --from=0 /artifacts ./
 
-ENV GRPC_EXPERIMENTAL_XDS_ENABLE_OVERRIDE_HOST=true
-
 ENTRYPOINT ["/csm_greeter_client"]

examples/cpp/csm/observability/Dockerfile.server

@@ -22,7 +22,7 @@ RUN ln -s /usr/bin/python3 /usr/bin/python
 RUN mkdir /artifacts
 
 COPY . .
-RUN OVERRIDE_BAZEL_VERSION=5.4.0 tools/bazel build //examples/cpp/csm/observability:csm_greeter_server
+RUN tools/bazel build //examples/cpp/csm/observability:csm_greeter_server
 RUN cp -rL /workdir/bazel-bin/examples/cpp/csm/observability/csm_greeter_server /artifacts/
 
 FROM python:3.9-slim-bookworm
@@ -34,6 +34,4 @@ RUN apt-get update \
 
 COPY --from=0 /artifacts ./
 
-ENV GRPC_EXPERIMENTAL_XDS_ENABLE_OVERRIDE_HOST=true
-
 ENTRYPOINT ["/csm_greeter_server"]

examples/cpp/csm/observability/README.md

@@ -1,6 +1,6 @@
 # gRPC C++ CSM Hello World Example
 
-This CSM example builds on the [Hello World Example](https://github.com/grpc/grpc/tree/master/examples/cpp/helloworld) and changes the gRPC client and server to accept configuration from an xDS control plane and test CSM observability.
+This CSM example builds on the [Hello World Example](https://github.com/grpc/grpc/tree/master/examples/cpp/helloworld) and changes the gRPC client and server to test CSM observability.
 
 ## Configuration