refac: early return for collectonly

[willemt]

No description provided.

[Copilot]

Pull Request Overview

This PR refactors the test execution flow to introduce an early return when operating in collect-only mode.

• Introduces an early return if previous_collectonly is truthy
• Removes the explicit invocation of _run_test_loop for non-collectonly mode

Comments suppressed due to low confidence (1)

pytest_asyncio_cooperative/plugin.py:312

• The early return for collectonly mode is now in place, but the removal of the _run_test_loop invocation means that when previous_collectonly is false, the cooperative test loop is never executed. Please verify that this change is intentional and that tests still run as expected in non-collectonly mode.

if previous_collectonly: