Add --no-install-recommends in dockerfile

Author: Bingjie Liu

Dockerfile

@@ -15,7 +15,7 @@ ENV BUILD_NUMBER ${BUILD_NUMBER:-1_0_0}
 
 RUN apt-get update && \
     apt-get -y upgrade && \
-    apt-get install -y curl && \
+    apt-get install -y --no-install-recommends curl && \
     rm -rf /var/lib/apt/lists/*
 
 ENV TZ=Europe/London