Update stdout writer usage to use std.fs.File

exercises/026_hello2.zig

@@ -16,12 +16,12 @@ const std = @import("std");
 //
 pub fn main() !void {
     // We get a Writer for Standard Out so we can print() to it.
-    const stdout = std.io.getStdOut().writer();
+    var stdout = std.fs.File.stdout().writer(&.{});
 
     // Unlike std.debug.print(), the Standard Out writer can fail
     // with an error. We don't care _what_ the error is, we want
     // to be able to pass it up as a return value of main().
     //
     // We just learned of a single statement which can accomplish this.
-    stdout.print("Hello world!\n", .{});
+    stdout.interface.print("Hello world!\n", .{});
 }

exercises/034_quiz4.zig

@@ -10,11 +10,11 @@ const std = @import("std");
 const NumError = error{IllegalNumber};
 
 pub fn main() void {
-    const stdout = std.io.getStdOut().writer();
+    var stdout = std.fs.File.stdout().writer(&.{});
 
     const my_num: u32 = getNumber();
 
-    try stdout.print("my_num={}\n", .{my_num});
+    try stdout.interface.print("my_num={}\n", .{my_num});
 }
 
 // This function is obviously weird and non-functional. But you will not be changing it for this quiz.