tested locally, works fine.
debian has supported riscv64 in the sid image for some time.
this is the same thing the carlosedp/golang image did.
this also fixes the bug with the wrong glibc version, as the build
container now uses the same glibc version as the final container.
GLIBC dependency issue highlighted in
https://github.com/shenxn/protonmail-bridge-docker/issues/79 is caused
by v3 of the bridge not supporting bionic. This PR simply updates the
"deb" version to match the "build" version which is already on
ubuntu:jammy.
