auto-format the code, and stop bothering with lines too long

[Skia]

Modern Python development practice include having the code auto-formatted by tools such as black or ruff.

Running these tools right now on the cdimage code show changes statistics that are a bit too scary to just go ahead at the eve of a release, hence I'm opening a bug instead of an MP.
❯ git diff --stat
[...]
 36 files changed, 4821 insertions(+), 3407 deletions(-)

This would avoid pointless CI runs [1] that take both CPU time, and dev time afterwards to manually try to find something that complies with the rules of pycodestyle.

[1]: like this one: https://launchpadlibrarian.net/787615356/buildlog_ci_ubuntu-cdimage_bb52d0902f179bcfc387f5332a551d4ff36e2ce4_BUILDING.txt.gz

[Michael Hudson-Doyle (mwhudson)]

Yes please.