Fix opening cover via emulated_hue without specifying a position

[Tho85]

Proposed change

Fix opening cover through emulated_hue without specifying position / brightness, i.e. with payload {"on":true}

#48367 introduced a bug in a code path that was not tested properly. The service variable would be overwritten in line 529, immediately before checking against it in line 530. So the statement following the if clause in line 531 would be unreachable. This PR reverts the change.

Regarding the tests: The two existing tests test_close_cover and test_set_position_cover would both supply a brightness / position to the API, so the modified code path was essentially untested and the bug would go unnoticed. I reused the first test to test the code path without a specified position.

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 #
• This PR is related to issue: Merge of nested IF-IF cases - E-G #48367
• Link to documentation pull request:

Checklist

• The code change is tested and works locally.
• Local tests pass. Your PR cannot be merged unless tests pass
• There is no commented out code in this PR.
• I have followed the development checklist
• The code has been formatted using Black (black --fast homeassistant tests)
• Tests have been added to verify that the new code works.

If user exposed functionality or configuration variables are added/changed:

• Documentation added/updated for www.home-assistant.io

If the code communicates with devices, web services, or third-party tools:

• The manifest file has all fields filled out correctly.
  Updated and included derived files by running: python3 -m script.hassfest.
• New or updated dependencies have been added to requirements_all.txt.
  Updated by running python3 -m script.gen_requirements_all.
• Untested files have been added to .coveragerc.

The integration reached or maintains the following Integration Quality Scale:

• No score or internal
• 🥈 Silver
• 🥇 Gold
• 🏆 Platinum

To help with the load of incoming pull requests:

• I have reviewed two other open pull requests in this repository.

[bdraco]

Thanks