签名失败了

安装MySQL8.0的时候遇到的问题，当时执行了

apt-get update的指令，然后出现了下面一大堆

Hit:1 https://download.docker.com/linux/ubuntu bionic InRelease
Hit:3 http://archive.ubuntu.com/ubuntu bionic InRelease
Get:4 http://repo.mysql.com/apt/ubuntu bionic InRelease [19.4 kB]
Err:4 http://repo.mysql.com/apt/ubuntu bionic InRelease
  The following signatures were invalid: EXPKEYSIG 8C718D3B5072E1F5 MySQL Release Engineering <mysql-build@oss.oracle.com>
Hit:5 http://archive.ubuntu.com/ubuntu bionic-updates InRelease
Hit:6 http://archive.ubuntu.com/ubuntu bionic-backports InRelease
Hit:2 https://www.rabbitmq.com/debian testing InRelease
Hit:7 http://archive.ubuntu.com/ubuntu bionic-security InRelease
Reading package lists... Done
W: GPG error: http://repo.mysql.com/apt/ubuntu bionic InRelease: The following signatures were invalid: EXPKEYSIG 8C718D3B5072E1F5 MySQL Release Engineering <mysql-build@oss.oracle.com>
E: The repository 'http://repo.mysql.com/apt/ubuntu bionic InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

对策

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 8C718D3B5072E1F5
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 58712A2291FA4AD5

MySQL的bug