Make WS command render_template not give up if initial render raises

[emontnemery]

Proposed change

Make WS command render_template not give up if initial render raises

Rationale:

As an example, WS command render_template will give up if referenced entity states.sensor.foo.state does not yet have a state when setting up template listeners for template {{ float(states.sensor.foo.state) + 1 }}. That's not wanted behavior and not in line with how template listeners in core works, for example in template entities.

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 #
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• Link to documentation pull request:

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[home-assistant]

Hey there @home-assistant/core, mind taking a look at this pull request as it has been labeled with an integration (websocket_api) you are listed as a code owner for? Thanks!

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[bdraco]

Nice that this goes away. This was only added for legacy backcompat in this place.

Hopefully nobody else is using it