add shadow helper method for UIKit

Author: mikhailChelbaev

Sources/ComponentsKit/Components/Card/UKCard.swift

@@ -141,10 +141,7 @@ extension UKCard {
       view.layer.cornerRadius = model.cornerRadius.value
       view.layer.borderWidth = 1
       view.layer.borderColor = UniversalColor.divider.cgColor
-      view.layer.shadowRadius = model.shadow.radius
-      view.layer.shadowOffset = model.shadow.offset
-      view.layer.shadowColor = model.shadow.color.cgColor
-      view.layer.shadowOpacity = 1
+      view.shadow(model.shadow)
     }
 
     static func contentView(_ view: UIView, model: Model) {

Sources/ComponentsKit/Shared/Types/Shadow.swift

@@ -1,4 +1,4 @@
-import Foundation
+import UIKit
 
 /// Defines shadow options for components.
 public enum Shadow: Hashable {
@@ -50,3 +50,14 @@ extension Shadow {
     }
   }
 }
+
+// MARK: - UIKit + Shadow
+
+extension UIView {
+  func shadow(_ shadow: Shadow) {
+    self.layer.shadowRadius = shadow.radius
+    self.layer.shadowOffset = shadow.offset
+    self.layer.shadowColor = shadow.color.cgColor
+    self.layer.shadowOpacity = 1
+  }
+}