Fix implicit nullable types to avoid PHP 8.4 warnings

Author: eiriksm

lib/Github/Client.php

@@ -123,7 +123,7 @@ class Client
      * @param string|null  $apiVersion
      * @param string|null  $enterpriseUrl
      */
-    public function __construct(Builder $httpClientBuilder = null, $apiVersion = null, $enterpriseUrl = null)
+    public function __construct(?Builder $httpClientBuilder = null, $apiVersion = null, $enterpriseUrl = null)
     {
         $this->responseHistory = new History();
         $this->httpClientBuilder = $builder = $httpClientBuilder ?? new Builder();

lib/Github/HttpClient/Builder.php

@@ -78,9 +78,9 @@ class Builder
      * @param StreamFactoryInterface|null  $streamFactory
      */
     public function __construct(
-        ClientInterface $httpClient = null,
-        RequestFactoryInterface $requestFactory = null,
-        StreamFactoryInterface $streamFactory = null
+        ?ClientInterface $httpClient = null,
+        ?RequestFactoryInterface $requestFactory = null,
+        ?StreamFactoryInterface $streamFactory = null
     ) {
         $this->httpClient = $httpClient ?? Psr18ClientDiscovery::find();
         $this->requestFactory = $requestFactory ?? Psr17FactoryDiscovery::findRequestFactory();

lib/Github/ResultPager.php

@@ -59,7 +59,7 @@ class ResultPager implements ResultPagerInterface
      *
      * @return void
      */
-    public function __construct(Client $client, int $perPage = null)
+    public function __construct(?Client $client, ?int $perPage = null)
     {
         if (null !== $perPage && ($perPage < 1 || $perPage > 100)) {
             throw new ValueError(sprintf('%s::__construct(): Argument #2 ($perPage) must be between 1 and 100, or null', self::class));