Refactor config flow tests in generic camera

[davet2001]

Proposed change

Clean up of existing tests:

• One redundant test removed.
• Use fixtures more to reduce total code size
• Rename some tests for consistency

Should be no functional change and no reduction in test coverage.

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:
• Link to documentation pull request:

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• The code change is tested and works locally.
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• The code has been formatted using Ruff (ruff format homeassistant tests)
• Tests have been added to verify that the new code works.

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[joostlek]

A common fixture for this is

@pytest.fixture
def mock_setup_entry() -> Generator[AsyncMock]:
    """Override async_setup_entry."""
    with patch(
        "homeassistant.components.airgradient.async_setup_entry",
        return_value=True,
    ) as mock_setup_entry:
        yield mock_setup_entry

This way you only need to load the fixture and its already patch. With the current solution, you would need to always do with mock_setup_entry (and I personally try to avoid them if possible)

[davet2001]

Ok thanks! Yes that makes sense. Will update tonight and check it.

[davet2001]

It works well, thanks!

Note: That has reduced the code but resulted in a lot of outdenting in facfe9e, so the diff looks a lot bigger. I suggest reviewing with whitespace ignored:
facfe9e?w=1

just a small nit, rest is ok