Update reduce to reduce:into for a bit faster running

[PaulTaykalo]

Few more milliseconds by using reduce

[SwiftLintBot]

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

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* Update reduce to reduce:into for a bit faster running.  
  [PaulTaykalo](https://github.com/PaulTaykalo)
  [#issue_number](https://github.com/realm/SwiftLint/issues/issue_number)

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[marcelofabri]

Thank you!