[CMake] Fix PackageModel target

Author: aciidgh

Sources/PackageModel/CMakeLists.txt

@@ -14,7 +14,7 @@ add_library(PackageModel
   Platform.swift
   Product.swift
   ResolvedModels.swift
-  Resources.swift
+  Resource.swift
   Sources.swift
   Target.swift
   ToolsVersion.swift)