Fix race in starting reauth flows

[bdraco]

Proposed change

Fix a race stating reauth flows

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)
• 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

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
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• The code has been formatted using Black (black --fast homeassistant tests)
• Tests have been added to verify that the new code works.

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• Documentation added/updated for www.home-assistant.io

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[emontnemery]

This looks much better 👍

[bdraco]

test failure is unrelated

FAILED tests/components/fritz/test_update.py::test_available_update_can_be_installed - AssertionError: assert 'unavailable' == 'on'

[bdraco]

mysql timeout test failure is unrelated