feat(review time): calculate average reviewer time for each review

[lwasser]

This will be useful data to have in our reviewer guide. to collect it we'd

1. parse all comments (i already have a last comment parser in the latest workflow) ut here we'd look for commnts that

look for:

Package Review and more importantly
Estimated hours spent reviewing: 6 

Then grab the number which represents hours.. It might be useful to simply add this to our review.yml file which would mean adding the review parsing functionality to pyosMeta)