Fix Fan template loosing percentage/preset

[frenck]

Proposed change

Fixes an issue reported in #67266.

Template fans update their preset/percentage based on template changes (e.g., a used entity in that template changes). However, in the current situation, when turning off a template fan, it will also reset the internal preset/percentage values.

This causes issues when turning on the fan later, as it would have reset preset/percentage, which isn't corrected until the template rendering re-triggers.

This change makes it behave consistently and as expected.

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 fan.turn_on not behaving in expected way #67266
• This PR is related to issue:
• Link to documentation pull request:

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[probot-home-assistant]

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

This is safe now that we dropped the legacy fan speeds

#67266 (comment)