[ci] arduino/setup-protoc@v1 API rate limit exceeded for 52.238.27.195

[bkontur]

E.g,: failed job

Error: Error: API rate limit exceeded for 52.238.27.195. (But here's the good news: Authenticated requests get a higher rate limit. Check out the documentation for more details.)

We use this for check-migrations.yml and runtime-matrix will just grow with adding new SP runtimes (e.g. people, coretime, ...).

How to fix? Add that authentication? Or install some prerequisites just once before matrix job runs (not sure if possible)?

I guess, we need that protoc or can be removed?

[ggwpez]

duplicate of #136

I guess, we need that protoc or can be removed?

Substrate wont build without.