Prevent "Implicitly marking parameter $version as nullable is deprecated" warning

Fixes #29

Author: thekid

ChangeLog.md

@@ -3,6 +3,9 @@ AWS Lambda change log
 
 ## ?.?.? / ????-??-??
 
+* Fixed issue #29: Implicitly marking parameter as nullable is deprecated
+  (@thekid)
+
 ## 7.0.0 / 2026-02-14
 
 This major release migrates to Amazon Linux 2023. Amazon Linux 2 end of

src/main/php/xp/lambda/Runner.class.php

@@ -44,15 +44,15 @@
  * Packaging will always include the `vendor` directory automatically.
  */
 class Runner {
-  const PHP_RELEASES = 'https://www.php.net/releases/';
+  const PHP_RELEASES= 'https://www.php.net/releases/';
 
   /** Fetches JSON for a given URL */
   private static function fetch(string $query) {
     return Json::read(new StreamInput((new HttpConnection(self::PHP_RELEASES.'?'.$query))->get()->in()));
   }
 
   /** Resolves the PHP version */
-  private static function resolve(string $version= null): string {
+  private static function resolve(?string $version= null): string {
     if (null === $version) {
       $select= ['version' => PHP_VERSION];
     } else if ('latest' === $version) {