Upgrade swift-syntax to 602.0.0 (#77)

Author: bfahey

Package.swift

@@ -20,7 +20,7 @@ let package = Package(
     dependencies: [
         .package(
             url: "https://github.com/swiftlang/swift-syntax.git",
-            exact: "600.0.0"
+            from: "602.0.0"
         ),
     ],
     targets: [