Fix missing UIKit import

[lucdion]

No description provided.

[codecov-io]

Codecov Report

Merging #56 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master      #56   +/-   ##
=======================================
  Coverage   96.28%   96.28%           
=======================================
  Files          22       22           
  Lines        4226     4226           
=======================================
  Hits         4069     4069           
  Misses        157      157

Impacted Files	Coverage Δ
Sources/PinLayoutImpl.swift	87.8% <ø> (ø)	⬆️

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