protobuf/kokoro/linux/prepare_build_linux_rc

#!/bin/bash

# Source this rc script to prepare the environment for Linux builds

# Set up dotnet
sudo sh -c 'echo "deb [arch=amd64] https://packages.microsoft.com/repos/microsoft-ubuntu-trusty-prod trusty main" > /etc/apt/sources.list.d/dotnetdev.list'
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys EB3E94ADBE1229CF
sudo apt-get update
# We use the .NET Core SDK 2.x to build...
sudo apt-get install -y dotnet-sdk-2.1.3
# But we also need the 1.x framework to test against, as we
# target netstandard1.x
sudo apt-get install -y dotnet-sharedframework-microsoft.netcore.app-1.0.5