Fix RemovePaintState benchmarks

[ryanhamley]

Launch Checklist

• briefly describe the changes in this PR
  • Iterates over individual removePaintState benchmark tests
  • fixes Benchmarks are broken by RemovePaintState benchmark #7927

[peterqliu]

@ryanhamley Changes look good and the bench throws an error as expected 👍 how do we resolve the removePaintState$1 error now that it's no longer silent?

[ryanhamley]

@peterqliu You should see the error twice now, once for master and once for the latest release branch. Merging this to master should publish a new version of that to S3 so we'll be down to 1 error. Unfortunately, that won't be resolved until we publish our next release in a couple weeks.

You can work around the release branch for the time being by changing https://github.com/mapbox/mapbox-gl-js/blob/master/bench/versions/index.html#L22 to .then(pkg => [ 'master']))