Optimizing Dockerfile (#8390)

packaging/docker/Dockerfile

@@ -4,20 +4,18 @@ WORKDIR /root
 
 ARG pkgFile
 ARG dirName
-RUN echo ${pkgFile}
-RUN echo ${dirName}
+RUN echo ${pkgFile} && echo ${dirName}
 
 COPY ${pkgFile} /root/
 RUN tar -zxf ${pkgFile}
 WORKDIR /root/${dirName}/
 RUN /bin/bash install.sh -e no
 
-RUN apt-get clean && apt-get update && apt-get install -y locales
-RUN locale-gen en_US.UTF-8
-ENV LD_LIBRARY_PATH="$LD_LIBRARY_PATH:/usr/lib"
-ENV LC_CTYPE=en_US.UTF-8
-ENV LANG=en_US.UTF-8
-ENV LC_ALL=en_US.UTF-8
+RUN apt-get clean && apt-get update && apt-get install -y locales && locale-gen en_US.UTF-8
+ENV LD_LIBRARY_PATH="$LD_LIBRARY_PATH:/usr/lib" \
+    LC_CTYPE=en_US.UTF-8 \
+    LANG=en_US.UTF-8 \
+    LC_ALL=en_US.UTF-8
 
 EXPOSE 6030 6031 6032 6033 6034 6035 6036 6037 6038 6039 6040 6041 6042
 CMD ["taosd"]