docs: update docker build command

CMakeLists.txt

@@ -31,7 +31,7 @@ endmacro()
 set(VERSION "")
 git_tag(VERSION)
 if(VERSION STREQUAL "")  # without git tag
-    message(FATAL_ERROR "Git command not found")
+    message(FATAL_ERROR "Unable to get version information")
 endif()
 
 ###############################################################

README.md

@@ -605,16 +605,20 @@ sys     0m0.005s
 
 ```bash
 $ git clone https://github.com/dnomd343/ClearDNS.git
-···
 $ cd ./ClearDNS/
 $ docker build -t cleardns .
-···
 ```
 
 ### 交叉构建
 
 ```bash
-docker buildx build -t dnomd343/cleardns --platform="linux/amd64,linux/arm64" https://github.com/dnomd343/ClearDNS.git --push
+$ git clone https://github.com/dnomd343/ClearDNS.git
+$ cd ./ClearDNS/
+$ docker buildx build
+    -t dnomd343/cleardns \
+    -t ghcr.io/dnomd343/cleardns \
+    -t registry.cn-shenzhen.aliyuncs.com/dnomd343/cleardns \
+    --platform="linux/amd64,linux/arm64" . --push
 ```
 
 ## 许可证