brave-browser: `repomd.xml` is not signed message on OpenSuse

Description

Public key is not signed message on OpenSuse

Steps to Reproduce

1. Run the following commands

sudo rpm --import https://brave-browser-rpm-release.s3.brave.com/brave-core.asc

cat << EOF | sudo tee /etc/zypp/repos.d/brave-browser-release.repo
[brave-browser-release]
name=Brave Browser Release Channel repository
baseurl=https://brave-browser-rpm-release.s3.brave.com/x86_64/
enabled=1
EOF

sudo zypper  install brave-keyring brave-browser

1. Console throws message saying public key is not signed

Actual result:

Expected result:

Should not throw any error message

Reproduces how often:

Eay

Brave version (brave://version info)

Release

Reproducible on current release:

• Does it reproduce on brave-browser dev/beta builds? Yes

Website problems only:

• Does the issue resolve itself when disabling Brave Shields?
• Is the issue reproducible on the latest version of Chrome?

Additional Information

Possibly similar to #3617 Same error shown for beta/dev/nightly install as well. cc: @mbacchi @bkero