Add benchmarking test to Actions workflows

[medley56]

Add a benchmarking script as a Github action that executes on PR updates, similar to the unit tests and linting. This script should do a basic check to make sure that the performance of the library is not drastically hampered by recent changes and will serve as a way to measure performance gains from planned performance enhancement changes.

[medley56]

@greglucas I assigned this to you because I think you already have a script that does some level of benchmarking. It could be neat to benchmark both "headers only" and also "full packet parsing" for a known data file and packet structure. We can put a tolerance on the amount of acceptable variance in parsing time and fail if the threshold is crossed.