Desktop Chrome can't run the scripts in browserscripts/browser

[gmierz]

When we try to run google chrome with browsertime in production we currently hit the following error where we are expecting an entry for the results from the browsescripts/browser scripts: https://treeherder.mozilla.org/#/jobs?repo=try&tier=1%2C2%2C3&revision=44499dec1880e5a4fe86cad3fb7fed94980b5bcd&selectedJob=270330459

The following directory contains the scripts which were not run: https://github.com/mozilla/browsertime/tree/master/browserscripts/browser

If it helps, this occurs on Google Chrome v76.0.3809.132.

[ncalexan]

This will be fallout from #31. I asked @hawkinsw to take a peek; I don't expect it to be tough to address.

[hawkinsw]

@ncalexan is exactly correct. This is not difficult to address. The issue is a misplaced catch -- it is one level of indirection too "high" which means that if one script in a category fails, the remaining scripts are not executed. I will put together the patch tomorrow and then publish a PR. Sorry about this.