Fixed OTEL_HOST variable name.

Author: zlogic

content/en/docs/refguide/runtime/tracing-in-runtime.md

@@ -219,7 +219,7 @@ for example, `mx-jaeger.example-namespace.svc.cluster.local`.
 To send logs and traces from a Mendix on Kubernetes environment to an OpenTelemetry collector, set the _Custom JVM Options_ to :
 
 ```
--javaagent:/opt/mendix/runtime/agents/opentelemetry-javaagent.jar -Dotel.javaagent.extensions=/opt/mendix/runtime/agents/mendix-opentelemetry-agent-extension.jar -Dotel.service.name=${APP_NAME} -Dotel.exporter.otlp.traces.endpoint=http://${OTEL_HOSTPORT}:4318/v1/traces -Dotel.exporter.otlp.traces.protocol=http/protobuf
+-javaagent:/opt/mendix/runtime/agents/opentelemetry-javaagent.jar -Dotel.javaagent.extensions=/opt/mendix/runtime/agents/mendix-opentelemetry-agent-extension.jar -Dotel.service.name=${APP_NAME} -Dotel.exporter.otlp.traces.endpoint=http://${OTEL_HOST}:4318/v1/traces -Dotel.exporter.otlp.traces.protocol=http/protobuf
 ```
 
 Replace `${APP_NAME}` with a meaninful identifier for your environment (service), and `${OTEL_HOST}` with the hostname of the OpenTelemetry Collector.