Continue on template error during yaml import for generic

[davet2001]

Proposed change

During yaml import for generic (camera), a check is done on the still_image_url. But the check can fail if this url contains a template referring to an entity which is not yet initialized at that point in the startup.

This change is to allow TemplateErrors to occur during yaml import, on the assumption that the original yaml was valid.

If it turns out to be invalid after all, it is not a huge problem. The user can still tinker with it in the configuration section of the UI, and the checks will be done (the errors are only ignored during yaml import).

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
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• 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 YAML import can fail if there are templates in still_image_url for generic #69402
• This PR is related to issue:
• Link to documentation pull request:

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[balloob]

Why do we even care if the template renders to something valid? We can just import it and the errors will show up when it tries to render the initialized entity.

[davet2001]

For YAML import I don't think it matters to ignore it. For when a user just typed it in the UI, my aim was to tell them if it was invalid with a UI message (so they can see the error on the UI rather than having to watch the log).