Update to swift-syntax 601.0.1 (#27)

Author: Mx-Iris

Package.resolved

@@ -15,7 +15,7 @@ let package = Package(
     dependencies: [
         .package(
             url: "https://github.com/swiftlang/swift-syntax.git",
-            from: "600.0.1"
+            from: "601.0.1"
         ),
         .package(url: "https://github.com/swiftlang/swift-docc-plugin", from: "1.3.0"),
         .package(url: "https://github.com/SwiftPackageIndex/SPIManifest.git", from: "0.12.0"),

Package.swift

@@ -22,7 +22,7 @@ public struct SimpleType: TypeProtocol {
     /// `Dictionary<Int, String>` it would be `["Int", "String"]`).
     public var genericArguments: [Type]? {
         _baseSyntax.genericArgumentClause.map { clause in
-            clause.arguments.map(\.argument).map(Type.init)
+            clause.arguments.map(\.argument).compactMap { $0.as(TypeSyntax.self).map(Type.init) }
         }
     }
 }