Improve ability to debug one time listeners blocking the event loop

[bdraco]

Proposed change

Improve ability to debug one time listeners blocking the event loop. I couldn't tell where the slow code was before because the repr wasn't very helpful before.

before 2024-02-08 16:51:10.120 WARNING (MainThread) [asyncio] Executing <Handle _OneTimeListener.async_call(<Event homeassistant_started[L]>) created at /Users/bdraco/home-assistant/homeassistant/core.py:601> took 2.074 seconds

after 2024-02-08 16:58:28.981 WARNING (MainThread) [asyncio] Executing <Handle _OneTimeListener(hass=<HomeAssistant RUNNING>, listener=<function async_setup.<locals>._async_initialize at 0x10ff2be20>, remove=None)(<Event homeassistant_started[L]>) created at /Users/bdraco/home-assistant/homeassistant/core.py:601> took 1.992 seconds

Type of change

• [ ] Dependency upgrade
• [ ] Bugfix (non-breaking change which fixes an issue)
• [ ] New integration (thank you!)
• [ ] New feature (which adds functionality to an existing integration)
• [ ] Deprecation (breaking change to happen in the future)
• [ ] Breaking change (fix/feature causing existing functionality to break)
• [x] Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
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