go: cannot find main module； see ‘go help modules‘问题解决

go: cannot find main module; see ‘go help modules’

Goland go默认管理依赖的方式变成了go module模式，更改GO111MODULE为off

				go env -w GO111MODULE=off

具体详情：

https://blog.csdn.net/sinat_28371057/article/details/109763938