Fix description

Author: tvdijen

tests/Assert/PositiveIntegerTest.php

@@ -43,7 +43,7 @@ public static function providePositiveInteger(): array
             'empty' => [false, ''],
             'valid positive integer' => [true, '123456'],
             'valid signed positive integer' => [true, '+123456'],
-            'valid zero' => [false, '0'],
+            'invalid zero' => [false, '0'],
             'valid negative leading zeros' => [true, '0000000000000000000005'],
             'invalid with fractional' => [false, '1.'],
             'invalid negative' => [false, '-1234'],

tests/Type/PositiveIntegerValueTest.php

@@ -43,7 +43,7 @@ public static function providePositiveInteger(): array
             'empty' => [false, ''],
             'valid positive integer' => [true, '123456'],
             'valid signed positive integer' => [true, '+123456'],
-            'valid zero' => [false, '0'],
+            'invalid zero' => [false, '0'],
             'valid negative leading zeros' => [true, '0000000000000000000005'],
             'valid with whitespace collapse' => [true, " 1 234 \n"],
             'invalid with fractional' => [false, '1.'],