Fix false positive in UnusedCaptureListRule

[daltonclaybrook]

Fixes concern raised by @jpsim here.

An array literal was being mistaken for a capture list in some cases.

[SwiftLintBot]

	1 Warning
⚠️	Please include a CHANGELOG entry to credit yourself! You can find it at CHANGELOG.md.

	15 Messages
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📖	This PR fixed a violation in Kickstarter: /Users/vsts/agent/2.150.0/work/1/s/osscheck/Kickstarter/Kickstarter-iOS/Views/Controllers/ProjectPamphletContentViewControllerTests.swift:224:8: warning: Unused Capture List Violation: Unused reference Device.phone4_7inch in a capture list should be removed. (unused_capture_list)
📖	This PR fixed a violation in Kickstarter: /Users/vsts/agent/2.150.0/work/1/s/osscheck/Kickstarter/Kickstarter-iOS/Views/Controllers/ProjectPamphletContentViewControllerTests.swift:224:29: warning: Unused Capture List Violation: Unused reference Device.phone5_8inch in a capture list should be removed. (unused_capture_list)
📖	This PR fixed a violation in Kickstarter: /Users/vsts/agent/2.150.0/work/1/s/osscheck/Kickstarter/Kickstarter-iOS/Views/Controllers/ProjectPamphletContentViewControllerTests.swift:224:50: warning: Unused Capture List Violation: Unused reference Device.pad in a capture list should be removed. (unused_capture_list)

Here's an example of your CHANGELOG entry:

* Fix false positive in UnusedCaptureListRule.  
  [daltonclaybrook](https://github.com/daltonclaybrook)
  [#issue_number](https://github.com/realm/SwiftLint/issues/issue_number)

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[jpsim]

Changelog entry isn't necessary because this rule hasn't shipped in a release yet.

[jpsim]

🎉 epic, thanks for fixing so quickly. Let's just remove the unnecessary changelog entry and I'll merge.