docker login 错误
ubuntu 18.04上执行 docker login 登录镜像仓库的时候，抛出如下异常：
Remote error from secret service: org.freedesktop.DBus.Error.UnknownMethod: No such interface ‘org.freedesktop.Secret.Collection’ on object at path /org/freedesktop/secrets/collection/login
Error saving credentials: error storing credentials - err: exit status 1, out: No such interface 'org.freedesktop.Secret.Collection' on object at path /org/freedesktop/secrets/collection/login
产生原因：apt包管理器安装docker-compose时装上的golang-docker-credential-hepers造成的错误。
解决办法：apt purge golang-docker-credential-helpers
当docker push时报如下错误：
denied: requested access to the resource is denied
解决方法：需要在给镜像打上仓库标签，比如用户名docker tag my-redis grnleaf/my-redis，然后再push上传。