Add brew-run-configure.sh to contributions, attempt number 2

I screwed up the branch I was originally going to send this from, so instead it's coming from a third branch. Anyway, differences between this and #16248 include:

- Being from a non-master branch
- I have now included directories for testing my script in (this was something @adamv was unsure about last time)
- The script now has more logging and comments, and does its checks better.