Fix next change (scheduler) sensors in AVM FRITZ!SmartHome

[mib1185]

Proposed change

You can set up a scheduler on the device, were you define, whether the eco or comfort temperature should be active or disable the scheduler at all. The api return the "nextchange" timestamp and temperature. When the scheduler is disabled, the nextchange timestamp will be 0, but the nextchange temperature is still set to the comfort temperature.

With this PR the nextchange timestamp is now used to consider the correct current and next preset sensors - these sensors will no be set to unknown (None) when the scheduler is disabled to reflect the real scheduler configuration.

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: Use temperature of current preset when set fritz HVAC mode to HEAT #126044
• Link to documentation pull request:

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[home-assistant]

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

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[mib1185]

these two properties do not exists on the original FritzDevice, therefore they don't need to be mocked