Bump httpcore to fix Python 3.14 tests

[hugovk]

Fixes #3576.

This is now fixed and released in httpcore 1.0.8:

• Fix AttributeError when importing on Python 3.14 encode/httpcore#1005
• Version 1.0.8 encode/httpcore#1006
• https://github.com/encode/httpcore/releases/tag/1.0.8

Updated in the lockfile by running uv lock --upgrade-package httpcore.

[illia-v]

@hugovk thank you for fixing the issue, I'm happy to see all the jobs green again!
I dropped the changelog entry because we don't usually add them for dev dependencies.

There is a $100 bounty for fixing the issue, feel free to submit an expense to our Open Collective.

[hugovk]

Thanks! I don't need the bounty, I did the work as part of my day job; is it possible to donate it to a charity to help Ukraine?

If this means a urllib3 team member claims it, and they need to pay taxes/fees as part of claiming it, so the actual donation is less than $100, then that's of course totally fine.

[illia-v]

@hugovk thanks for the hard work for the Python community!

I appreciate your choice to donate the money to help Ukraine ❤️. Give me a few days to evaluate options