fix: add prometheus to the runtime image (#2565)

Author: hhzhang16

container/Dockerfile.vllm

@@ -462,12 +462,15 @@ RUN apt-get update && \
         cuda-toolkit-12-8 && \
     rm -rf /var/lib/apt/lists/*
 
-### COPY NATS & ETCD ###
+### COPY NATS & ETCD & PROMETHEUS ###
 # Copy nats and etcd from base image
 COPY --from=base /usr/bin/nats-server /usr/bin/nats-server
 COPY --from=base /usr/local/bin/etcd/ /usr/local/bin/etcd/
 ENV PATH=/usr/local/bin/etcd/:$PATH
 
+# Copy prometheus from base image
+COPY --from=base /usr/local/bin/prometheus /usr/local/bin/prometheus
+
 # Copy UCX from base image as plugin for NIXL
 # Copy NIXL source from wheel_builder image
 # Copy dynamo wheels for gitlab artifacts