我正在尝试使用该sudo apt update命令，但一直收到以下错误：
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.
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://dl.google.com/linux/chrome/deb stable InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY E88979FB9B30ACF2
因此，我无法继续更新。
我该如何解决这个错误？