mitigate protocolbuffers/protobuf#19558

[nickbreen]

at least until it's addressed upstream

protocolbuffers/protobuf#19558

[nickbreen]

Should be able to use https://github.com/aspect-build/toolchains_protoc but having difficulty getting it to work.

[nickbreen]

Because one needs hackery to do so.

protocolbuffers/protobuf#19679

aspect-build/toolchains_protoc#47

TL;DR: need upstream rules modules to support toolchain resolution

[nickbreen]

Instructions on using the unused-deps_deploy.jar release artifact now included.