As per section 13.a of the Hyperledger Charter all code submitted to the Hyperledger Foundation needs to have a Developer Certificate of Origin (DCO) sign-off.
The sign off needs to be using your legal name, not a pseudonym. Git has a built-in mechanism to allow this with the -s or --signoff argument to git commit command, providing your user.name and user.email have been setup correctly.
If you have any questions, you can reach us on Besu chat; first, join the Discord server then join the Besu channel.