resolve GPG error: The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY AED4B06F473041FA
获取key
gpg --keyserver pgp.mit.edu --recv-keys AED4B06F473041FA
添加key
gpg --armor --export AED4B06F473041FA| apt-key add -
然后再更新
apt-get update
