Fix translation string in tankerkoenig

[j4n-e4t]

Breaking change

Proposed change

Add missing translation string to tankerkoenig integration.
Links to #127811

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
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• 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: Help wanted: fix missing translation strings #127811
• Link to documentation pull request:

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[home-assistant]

Hey there @guillempages, @mib1185, @jpbede, mind taking a look at this pull request as it has been labeled with an integration (tankerkoenig) you are listed as a code owner for? Thanks!

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[mib1185]

Hi @j4n-e4t
thanks for contributing this 👍The change itself looks good 👍
I think we should rework the options flow, because an invalid auth during the options flow will end up in a dead lock for the user, since it is not possible to fix such issue within the options flow 🤔 But this is something for a later PR