Fix Implicitly marking parameter $maxItems as nullable is deprecated

Author: bytestream

src/ArrayAssertsTrait.php

@@ -158,7 +158,7 @@ public static function arrayHasKeyWith($key, $constraint): ArrayHasKeyWith
     public static function assertSequentialArray(
         $array,
         int $minItems,
-        int $maxItems = null,
+        ?int $maxItems = null,
         $constraint = null,
         bool $ignoreKeys = false,
         string $message = ''
@@ -185,7 +185,7 @@ public static function assertSequentialArray(
      */
     public static function sequentialArray(
         int $minItems,
-        int $maxItems = null,
+        ?int $maxItems = null,
         $constraint = null,
         bool $ignoreKeys = false
     ): SequentialArray {