Improved error handling for oauth2 configuration in onedrive integration

[wmoss]

Proposed change

As described in much more detail in PR #154579 and this blog post, previously, if there was no internet and the call to fetch cloud services fail, integrations like this one using cloud oauth2 would terminally fail. #154579 introduced config_entry_oauth2_flow.ImplementationUnavailableError and raises it in that specific case. This catches that error and raises ConfigEntryNotReady so that the configuration will be retried when internet is available again.

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: Fix account link no internet on startup #154579
• Link to documentation pull request:
• Link to developer documentation pull request:
• Link to frontend pull request:

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[home-assistant]

Hey there @zweckj, mind taking a look at this pull request as it has been labeled with an integration (onedrive) you are listed as a code owner for? Thanks!

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