Update SnapKit.podspec* Tag 5.7.1

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Fix podspec tagged version (#748)Co-authored-by: Robert Payne <robertjpayne@Roberts-MacBook-Pro.local>

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Release v3.2.0 (#403)* make 'layoutConstraints' public again (#382)* Fix wrong function call within contentCompressionResistanceHorizontalPriority (#387)* Missing property topMargin on ConstraintMakerExtendable (#393)This pull request adds the missing property "topMargin" to ConstraintMakerExtendable class.* Switched main target build settings' "skip install" default settings to YES. (#391)* Add an isActive API to Constraint* Priority enum (#345)* Adds ConstraintPriority enum to ConstraintMakerPrioritizable* Constraints priority is now more robust* Adds priority enum function* Fixes compile error* Adds failable initializer. Custom macOS medium priority. Adds back deleted methods* Updates depracation messages* Improve Priority API's* Add extra protocol conformances to ConstraintPriority* Tweak priority API's for offseting* Tweak priority API's some more and add tests* Prepare for release

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