Support XCSkipTests under Mac Catalyst

[fhasse95]

This PR updates the generated XCSkipTests harness to include Mac Catalyst.

Related PRs:

• Support XCSkipTests under Mac Catalyst skip#724
• Load host FFI libraries for Mac Catalyst tests skip-ffi#11

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Please review the contribution guide at https://skip.dev/docs/contributing/ for advice and guidance on making high-quality PRs.

Skip Pull Request Checklist:

• REQUIRED: I have signed the Contributor Agreement
• REQUIRED: I have tested my change locally with swift test
• OPTIONAL: I have tested my change on an iOS simulator or device
• OPTIONAL: I have tested my change on an Android emulator or device

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• AI was used to generate or assist with generating this PR. Please specify below how you used AI to help you, and what steps you have taken to manually verify the changes.

AI was used to help identify the Catalyst/Robolectric host-library issue and draft the changes. Afterwards, I manually reviewed the code and verified the affected XCSkipTests from a Mac Catalyst test target.

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