chatbot-rag-app: updates README to warn about quoting hazard (elastic#461)

Co-authored-by: Anuraag (Rag) Agrawal <[email protected]>

Author: codefromthecrypt

example-apps/chatbot-rag-app/README.md

@@ -89,6 +89,11 @@ ELASTICSEARCH_URL=http://elasticsearch.default.svc:9200
 OTEL_EXPORTER_OTLP_ENDPOINT=http://otel-collector.default.svc:4318
 ```
 
+*Note*: Do not add quotes to your `.env` file, as they are loaded raw in
+Kubernetes.
+Do this: `OTEL_EXPORTER_OTLP_HEADERS=Authorization=Bearer xyz`
+Not this: `OTEL_EXPORTER_OTLP_HEADERS="Authorization=Bearer xyz"`
+
 Then, import your `.env` file as a configmap like this:
 ```bash
 kubectl create configmap chatbot-rag-app-env --from-env-file=.env
@@ -249,4 +254,4 @@ docker compose up --build --force-recreate
 [docker-compose]: ../../docker/docker-compose-elastic.yml
 [edot-python]: https://github.com/elastic/elastic-otel-python
 [k8s-manifest-elastic]: ../../k8s/k8s-manifest-elastic.yml
-[uv]: https://docs.astral.sh/uv/getting-started/installation/
+[uv]: https://docs.astral.sh/uv/getting-started/installation/