This fixes all Python3 problems in scripts and tests running via
v8_presubmit.py. It includes:
- Test runner
- Release tools
- Perf runner
- Torque formatter
- V8's main presubmit

On bots, v8_presubmit is run with vpython, hence we also add
the required dependencies. After the Python3 migration, most
of the transitional code in this CL can be removed again.

Bug: chromium:1293709,chromium:1292016
Change-Id: Ic25e5965948b212c047e9d5194d2a4b6db1fa91b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3432213Reviewed-by: Liviu Rau <liviurau@chromium.org>
Commit-Queue: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/main@{#78936}