Bump all build go versions to v1.21.0
Bump the minimum build package version to v1.19.0
Debian "buster" is not longer supported. Security updates have been
discontinued since June 30th 2022. We will build using the latest
version, "bookworm".
As usual, we keep with the last two Go versions, which means the last
year of Go release (they release every 6 months or so).
This change means we can now use the type params (generics) in the
project!
Now that we have a base docker image that has all our RPC compilation
dependencies installed, we can also run the mobile RPC compilation
there. This removes the need to install falafel and goimports on the
local machine.
This commit aims to make it easier for developers to compile our
protobuf definitions. They now only need to have docker installed
instead of a whole set of binaries and libraries all pinned to very
specific versions.
