Fixes #140 - Don't count blocked_total for private/incognito tabs
I also started using async
for this considering we wanted to change to that anyway and it makes it a bit nicer.
I am currently getting one test failure on firefox:latest, but it looks totally unrelated to me: https://gitlab.com/evilpie/adblockpluschrome/-/jobs/767265618
Edited by Tom Schuster