Revert nest reloading due to lock up

[allenporter]

Breaking change

Proposed change

Partial revert of PR #62976. Don't reload the integration on pubsub messages since it can lock up Home Assistant.

This seems to have been resolved in March-era google-cloud-pubsub releases, and I was using newer versions initially locally testing this change locally. Noticed on a Supervised version of Hass when testing a dev build.

Home assistant is pinned to an older google-cloud-pubsub versions that are currently pinned to until #56669 is resolved because the home assistant wheel building process breaks GRPC on alpine.

See note in https://googleapis.dev/python/pubsub/latest/subscriber/api/futures.html#google.cloud.pubsub_v1.subscriber.futures.StreamingPullFuture.cancel about cancellation:

Changed in version 2.4.1: The method does not block anymore, it just triggers the shutdown and returns immediately. To block until the background stream is terminated, call result() after cancelling the future

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 #
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Checklist

• The code change is tested and works locally.
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• Tests have been added to verify that the new code works.

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[frenck]

Happy New Year @allenporter 🍾