Update examples

examples/file.sp

@@ -2,9 +2,9 @@ const io from @'core/io';
 const { open } from @'core/fs';
 
 let @main in {
-    io.out("What is your name? ");
+    io.out('What is your name? ');
     let name = io.in();
-    let file = open("name.txt");
+    let file = open('name.txt');
     file.write(name);
     file.close();
 }