Nonzero Exit Code for performance-setup Failures

[Tohron]

Created to address dotnet/performance#2010
This PR aims to cause performance-setup.ps1 and performance-setup.sh to return a nonzero exit code whenever a command in the script fails.

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[DrewScoggins]

@Tohron Since we have so much repeated code in these scripts from the error checking, I think that it would be useful to write a function that takes in the command we want to check, and then does the error level checking. This would greatly simplify the code, and make adding new checks much easier.