NO_PUBKEY when updating QGIS in Linux / Ubuntu (2022)

Update the key file (qgis-archive.gpg) by:

wget  -qO  -  https://qgis.org/downloads/qgis-2022.gpg.key  |  gpg  --no-default-keyring  --keyring  gnupg-ring:/etc/apt/trusted.gpg.d/qgis-archive.gpg  --import

The NO_PUBKEY error message will be gone for 'apt update'