gh-93671: Avoid exponential backtracking in deeply nested sequence patterns in match statements

[pablogsal]

closes: #93671

Should there be a test for this?

Should there be a test for this?

I submitted the PR so we can start checking that it works in other cases.

I will be adding a bunch of cases, but the tests are limited because there is nothing crashing, although I can add a bunch of cases that would take years to succeed.

I can confirm that the new test just doesn't finish on main without the patch. Since this is in the parser, it's also not something you can easily CTRL-C out of 😆

Thanks @pablogsal for the PR, and @ambv for merging it 🌮🎉.. I'm working now to backport this PR to: 3.10, 3.11.
🐍🍒⛏🤖

Sorry, @pablogsal and @ambv, I could not cleanly backport this to 3.10 due to a conflict.
Please backport using cherry_picker on command line.
cherry_picker 53a8b17895e91d08f76a2fb59a555d012cd85ab4 3.10

GH-93689 is a backport of this pull request to the 3.11 branch.

Are you preparing the backport or should I do it? @ambv

GH-93690 is a backport of this pull request to the 3.10 branch.

Thanks for the quick fix, @pablogsal!