Fix reloading the sun integration

[bdraco]

Proposed change

Fixes

2022-04-06 22:15:52 ERROR (MainThread) [homeassistant.core] Unable to remove unknown job listener _FilterableJob(job=<Job HassJobType.Callback <bound method Sun.loading_complete of <Entity Sun: above_horizon>>>, event_filter=None)
Traceback (most recent call last):
  File "/usr/src/homeassistant/homeassistant/core.py", line 986, in _async_remove_listener
    self._listeners[event_type].remove(filterable_job)
ValueError: list.remove(x): x not in list

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)
• Breaking change (fix/feature causing existing functionality to break)
• Code quality improvements to existing code or addition of tests

Additional information

• This PR fixes or closes issue: fixes #
• This PR is related to issue:
• Link to documentation pull request:

Checklist

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[probot-home-assistant]

Hey there @Swamp-Ig, mind taking a look at this pull request as it has been labeled with an integration (sun) you are listed as a code owner for? Thanks!
_{^{(message by CodeOwnersMention)}}

[bdraco]

I saw reports of the sun entity not being present on the forum so I added this as I wanted to validate the order of events given there is a comment in setup.py about being fragile https://github.com/home-assistant/core/blob/dev/homeassistant/setup.py#L264