alpine-ruby-protobuf-grpc-fix

This is fix for alpine linux protobuf+grpc segmentation fault

Basic steps:

• apk add --no-cache gcompat
• bundle config set --local force_ruby_platform true
• bundle config build.grpc --with-cflags=-D__va_copy=va_copy
• bundle config build.google-protobuf --with-cflags=-D__va_copy=va_copy
• bundle install --force (or bundle install)