Use relative path when storing beta tester file path

Author: DechengMa

Sources/FileSystem/Beta Tester/BetaTesterProcessor.swift

@@ -16,7 +16,7 @@ struct BetaTesterProcessor {
 
         try file.write(testers.renderAsCSV())
 
-        return file.name
+        return file.path(relativeTo: try Folder(path: FileManager.default.currentDirectoryPath))
     }
 }
 

Sources/FileSystem/Readers.swift

@@ -60,8 +60,7 @@ public enum Readers {
             }
 
             guard
-                let url = URL(string: "file://\(filePath)"),
-                let result = try? decoder.decode(T.self, from: url) else {
+                let result = try? decoder.decode(T.self, from: URL(fileURLWithPath: filePath)) else {
                     fatalError("Could not read CSV file: \(filePath)")
             }