docs: update readme to use goctl@cli (#1255)

* chore: update goctl version

* style: coding style

* docs: update readme to use goctl@cli

readme-cn.md

@@ -104,10 +104,10 @@ GO111MODULE=on GOPROXY=https://goproxy.cn/,direct go get -u github.com/tal-tech/
 
     ```shell
     # Go 1.15 及之前版本
-    GO111MODULE=on GOPROXY=https://goproxy.cn/,direct go get -u github.com/tal-tech/go-zero/tools/goctl
+    GO111MODULE=on GOPROXY=https://goproxy.cn/,direct go get -u github.com/tal-tech/go-zero/tools/goctl@cli
     
     # Go 1.16 及以后版本
-    go install github.com/tal-tech/go-zero/tools/goctl@latest
+    GOPROXY=https://goproxy.cn/,direct go install github.com/tal-tech/go-zero/tools/goctl@cli
     ```
 
     确保 goctl 可执行

readme.md

@@ -107,10 +107,10 @@ go get -u github.com/tal-tech/go-zero
 
    ```shell
    # for Go 1.15 and earlier
-   GO111MODULE=on go get -u github.com/tal-tech/go-zero/tools/goctl
+   GO111MODULE=on go get -u github.com/tal-tech/go-zero/tools/goctl@cli
    
    # for Go 1.16 and later
-   go install github.com/tal-tech/go-zero/tools/goctl@latest
+   go install github.com/tal-tech/go-zero/tools/goctl@cli
    ```
 
    make sure goctl is executable.