Remove 'tariff' edition from options-flow

[azogue]

Proposed change

TL;DR

The entry.data[ATTR_TARIFF] is what makes the entry.unique_id, so it's an incoherence to be able to change it in the Options flow.

Long version
There are only 2 tariffs, and it's a geographical option, so normally the user has only 1 entry, and does not play with that,

BUT, in this borderline-scenario:

• setup of 1st entry with tariff-1
• go to options and change to tariff-2 (it's unique ID doesn't change, and it's equal to tariff-1)
• setup a 2nd entry with tariff-1 ==> 🧨 Invalid, as already configured
• setup a 2nd entry with tariff-2 --> OK, setting unique_id=tariff-2, but the sensor it's the same as the 1st entry, and needs to go to options to swap tariff 💩🤪

So the best action to prevent that is to remove that option 🔥

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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[jbouwh]

Looks good to me!

[jbouwh]

Looks good!