remove warning of no x386 for Brave

Open apt file for Brave
sudo xed /etc/apt/sources.list.d/brave-browser-release.list
replace:
deb [signed-by=/usr/share/keyrings/brave-browser-archive-keyring.gpg] https://brave-browser-apt-release.s3.brave.com/ stable main
with:
deb [arch=amd64 signed-by=/usr/share/keyrings/brave-browser-archive-keyring.gpg] https://brave-browser-apt-release.s3.brave.com/ stable main
Run: sudo apt update

warning should be gone.