Fix typo for SPM

Author: mtfum

Package.swift

@@ -5,7 +5,7 @@ import PackageDescription
 
 let package = Package(
     name: "CustomAlbum",
-    platform: [.iOS(v11)]
+    platforms: [.iOS(.v11)],
     products: [
         // Products define the executables and libraries produced by a package, and make them visible to other packages.
         .library(