visionOS - Add the resource to Package.swift

Author: HaleXie

Package.swift

@@ -43,6 +43,7 @@ let package = Package(
             dependencies: ["InputBarAccessoryView"],
             path: "Sources",
             exclude: ["Supporting/Info.plist", "Supporting/MessageKit.h"],
+            resources: [.process("Assets.xcassets")],
             swiftSettings: [SwiftSetting.define("IS_SPM")]
         ),
         .testTarget(name: "MessageKitTests", dependencies: ["MessageKit"])