ruff-ecosystem: Add indico/indico repo (#9850)
It's a pretty big codebase using lots of different stuff, so a good
candidate for finding obscure problems.
I didn't look more closely which options are used (I have the feeling
`--select ALL` is not implied, since I see you adding it via
`check_options` for certain entries but not for others), the repo itself
has a pretty large ruff.toml - but assuming ecosystem just cares about
differences between base and head of a PR, `ALL` most likely makes
sense.
