Modify retracer script to output min requirements json diff After the ANGLE retracer script runs with the get_min_reqs option, ouptut the json file diff. Bug: b/42266279 Change-Id: Ia744e4e36fb9f8b7e8d498d44412af733c7ed9b1 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5874161 Commit-Queue: Cody Northrop <cnorthrop@google.com> Reviewed-by: Cody Northrop <cnorthrop@google.com>