Added time measurements for several actions

[MichalPavlik]

We want to know, how much time it takes for some actions.

[baronfel]

After this change goes out, I would like to coordinate with the actions/setup-dotnet repo to hook up verbose logging with the GitHub Actions step debug logging capability. Ideally, when a user opts into step-level debugging, we should enable verbose logging in the install scripts automatically. This would likely need to be done here, where the install scripts are actually invoked.