protoc-gen-go build instructions for CCA demo are confusing

[moconnor725]

in https://github.com/veraison/docs/blob/main/demo/cca/manual-end-to-end.md

"For build to succeed one needs to install following packages:
protoc-gen-go with version v1.26 Download protobuf-all-[VERSION].tar.gz from [here](https://github.com/protocolbuffers/protobuf/releases)."

"here" has no 1.26.
There is a version 26 but it has no protoc-gen-go

there is a protoc-gen-go over in https://github.com/golang/protobuf

But then there are instructions

./configure
make
make check
sudo make install

But it's not clear in what component that should be done.