valid html can have no white space before the first tag

JBlond · JBlond · commit 42b1ace4d5d6 · 2020-01-10T14:48:16.000+01:00
diff --git a/example/example.php b/example/example.php
@@ -24,9 +24,7 @@
 // Initialize the diff class.
 // \jblond\diff
 $diff = new Diff($a, $b, $options);
-?>
-
-<!DOCTYPE html>
+?><!DOCTYPE html>
 <html lang="en">
     <head>
         <meta charset="utf-8"/>
