added kubectl in dockerfile

Dockerfile

@@ -35,7 +35,12 @@ RUN cargo build --release && mv target/release/pod ./ && rm -rf target
 FROM debian:buster-slim
 COPY --from=cargo-build /usr/bin/docker /usr/bin/docker
 COPY --from=cargo-build /usr/src/pod/pod pod
-RUN DEBIAN_FRONTEND=noninteractive apt-get update && apt-get install -y libsqlcipher-dev && rm -rf /var/lib/apt/lists/*
+RUN DEBIAN_FRONTEND=noninteractive apt-get update && apt-get install -y libsqlcipher-dev curl && rm -rf /var/lib/apt/lists/*
+ARG use_kubernetes=false
+RUN if [ "$use_kubernetes" = "true" ] ; then \
+      curl -LO https://storage.googleapis.com/kubernetes-release/release/$(curl -s https://storage.googleapis.com/kubernetes-release/release/stable.txt)/bin/linux/amd64/kubectl \
+      && chmod +x ./kubectl  \
+      &&  mv ./kubectl /usr/local/bin/kubectl ; fi
 
 # Check that library versions match (sqlcipher, libc, etc)
 RUN ./pod --version 1>/dev/null 2>&1