Upgrade Tor Browser to 8.0a10
_Originally created by @intrigeri on [#15803 (Redmine)](https://public-redmine-archive.tails.boum.org/code/issues/15803)_
It’s not the final 8.0 but better detect now any breakage or adjustment
we need to do on our side.
- announce:
<https://lists.torproject.org/pipermail/tor-qa/2018-August/000947.html>
- known issues:
<https://trac.torproject.org/projects/tor/query?status=!closed&keywords=~ff60-esr&max=256>
Feature Branch: feature/15803-tor-browser-8.0a10+force-all-tests
### Related issues
- **Blocks** tails/accounting#15334
- **Blocks** tails/tails#15706
- **Blocks** tails/tails#15801
- **Blocks** tails/tails#15805
issue