Fix example code block padding for PHP 8.3+ (#1501)

Co-authored-by: Luffy <lufei@php.net>

styles/theme-base.css

@@ -948,6 +948,7 @@ div.tip p:first-child {
     overflow-x: auto;
 }
 
+.docs .example-contents > .phpcode > pre > code,
 .docs .example-contents > .phpcode > code {
     padding: .75rem;
 }