feat: raise a more specific exception on timeout

[nejch]

This provides a narrower exception to catch when calling wait_until_responsive.

Context: when an entire testsuite relies on a service, I'd like to call pytest.exit() if it times out so that a useful error message is displayed for the user instead of failing the fixture setup for all tests and producing a wall of text.

/cc @Luminaar

[augi]

May I ask you to resolve the conflicts? 🙏 Thanks!