I’m building my docker image from ubuntu:22.04

when run apt-get update it raise error

The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 871920D1991BC93C

I know that I can get the key from a repository by

gpg --keyserver hkp://keyserver.ubuntu.com --recv-keys 871920D1991BC93C

but there no gpg in my base image,so that if I dont update apt, it cannot verify PUBKEY, if I install gpg apt is not updated.

How can I do, SOS