Add total time to each test section

[williambdean]

For the #1158 automation, I would like to see the total time for each test section.
Will have to pull down the start and end time stamps with the endpoint and then make a
time difference. It might be best to use python for a human readable time difference.

Could also sort by the total time of something.

See human readable time implementation here: pymc-devs/pytensor#1125