Update template

I found out that C# 10 added file-scoped namespaces that don't need the whole thing to be wrapped in braces, so that's neat.

src/Template.cs

@@ -1,7 +1,7 @@
-namespace aoc2021
+namespace aoc2021;
+
+internal class DayTemplate
 {
-    internal class DayTemplate
-    {
     internal static void Go()
     {
         Logger.Log("Day #");
@@ -25,5 +25,4 @@
 
         Logger.Log($"part2: ");
     }
-    }
 }