Refactor TP-Link Omada config flow tests

[MarkGodwin]

Proposed change

Changes requested in #156697. This retains 100% coverage of the config flow, and improves the test quality.

I think this gets to bronze quality level. If this passes, I'll put in a PR to bump it.

Bronze

• action-setup - Service actions are registered in async_setup
• appropriate-polling - If it's a polling integration, set an appropriate polling interval
• brands - Has branding assets available for the integration
• common-modules - Place common patterns in common modules
• config-flow-test-coverage - Full test coverage for the config flow
• config-flow - Integration needs to be able to be set up via the UI
  • Uses data_description to give context to fields
  • Uses ConfigEntry.data and ConfigEntry.options correctly
• dependency-transparency - Dependency transparency
• docs-actions - The documentation describes the provided service actions that can be used
• docs-high-level-description - The documentation includes a high-level description of the integration brand, product, or service
• docs-installation-instructions - The documentation provides step-by-step installation instructions for the integration, including, if needed, prerequisites
• docs-removal-instructions - The documentation provides removal instructions
• entity-event-setup - Entity events are subscribed in the correct lifecycle methods
• entity-unique-id - Entities have a unique ID
• has-entity-name - Entities use has_entity_name = True
• runtime-data - Use ConfigEntry.runtime_data to store runtime data
• test-before-configure - Test a connection in the config flow
• test-before-setup - Check during integration initialization if we are able to set it up correctly
• unique-config-entry - Don't allow the same device or service to be able to be set up twice

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: N/A
• This PR is related to issue: N/A
• Link to documentation pull request: N/A
• Link to developer documentation pull request: N/A
• Link to frontend pull request: N/A

Checklist

• I understand the code I am submitting and can explain how it works.
• 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
• I have followed the perfect PR recommendations
• The code has been formatted using Ruff (ruff format homeassistant tests)
• Tests have been added to verify that the new code works.
• Any generated code has been carefully reviewed for correctness and compliance with project standards.

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.
• For the updated dependencies - a link to the changelog, or at minimum a diff between library versions is added to the PR description.

To help with the load of incoming pull requests:

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

[Copilot]

Pull request overview

This PR refactors the TP-Link Omada config flow tests in response to feedback from #156697, improving test quality while maintaining 100% test coverage. The refactoring removes patching of internal config flow functions and instead mocks external APIs, following Home Assistant testing best practices.

Key changes:

• Introduces proper test fixtures that mock the Omada client API instead of internal validation functions
• Consolidates multiple error handling tests into parametrized tests to reduce code duplication
• Adds controller ID validation during reauthentication to prevent users from reauthenticating with a different controller
• Updates quality scale status from "todo" to "done" for config-flow-test-coverage

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 2 comments.

File	Description
tests/components/tplink_omada/test_config_flow.py	Refactors config flow tests to mock external APIs, adds fixtures for test setup, consolidates error tests using parametrization, and improves test coverage verification
homeassistant/components/tplink_omada/config_flow.py	Adds controller ID validation in reauth flow to prevent reauthenticating with a different controller
homeassistant/components/tplink_omada/strings.json	Adds user-facing abort message for device mismatch during reauth
homeassistant/components/tplink_omada/quality_scale.yaml	Updates config-flow-test-coverage rule from todo to done status

[home-assistant]

Please take a look at the requested changes, and use the Ready for review button when you are done, thanks 👍

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