Round all floating point numbers in test output to a few digits

[sethrj]

This finishes up a little work I was doing earlier this month to make stringy results less sensitive to small numerical differences (including float vs double). It now rounds all floating point values in filtered string outputs to the specified number of digits (by default).

[github-actions[bot]]

Test summary

 4 401 files   6 736 suites   13m 12s :stopwatch:  1 805 tests  1 796 :white_check_mark:  9 :zzz: 0 :x: 23 009 runs  22 924 :white_check_mark: 85 :zzz: 0 :x:

Results for commit e13be06d.

:recycle: This comment has been updated with latest results.