Fix charging settings mock

[rikroe]

Proposed change

Due to https://github.com/home-assistant/core/pull/97895 failing I found an error in my remote service mock for charging settings.

Type of change

• [x] Bugfix (non-breaking change which fixes an issue)
• [ ] New feature (which adds functionality to this library)
• [ ] 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:

Checklist

• [x] The code change is tested and works locally.
• [x] Tests have been added to verify that the new code works.

[codecov[bot]]

Codecov Report

Patch and project coverage have no change.

Comparison is base (95cd1de) 100.00% compared to head (4b5ee1e) 100.00%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #554 +/- ## ========================================= Coverage 100.00% 100.00% ========================================= Files 18 18 Lines 1504 1504 ========================================= Hits 1504 1504 ``` | Flag | Coverage Δ | | |---|---|---| | 3.10 | `100.00% <ø> (ø)` | | | 3.11 | `100.00% <ø> (ø)` | | | 3.7 | `100.00% <ø> (ø)` | | | 3.8 | `100.00% <ø> (ø)` | | | 3.9 | `100.00% <ø> (ø)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=bimmerconnected#carryforward-flags-in-the-pull-request-comment) to find out more.

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