bump anyio version

[ebetica]

tests:

$ (uv venv test-anyio-4 && source test-anyio-4/bin/activate && uv pip install "anyio>=4.0,<5.0" pytest curio trio overly && uv pip install -e . && python -m pytest)
$ (uv venv test-anyio-3 && source test-anyio-3/bin/activate && uv pip install "anyio>=3.0,<4.0" pytest curio trio overly && uv pip install -e . && python -m pytest)

tests currently fail actually, but I think it's using a trio api that's deprecated

[Cheaterman]

Can we please get this merged and publish a new version? The test that fails is indeed because anyio < 4.0 breaks on recent versions of trio, which is very painful for my apps.

@theelous3 Hello? :-)

[theelous3]

I'll look today, cheers. Sorry was very afk :)

[Cheaterman]

@theelous3 Thanks in advance :)

EDIT: And glad to see you're OK, I was worried for a moment haha