fix: PHPStan errors appear

tests/system/Validation/ValidationTest.php

@@ -21,6 +21,7 @@
 use CodeIgniter\Validation\Exceptions\ValidationException;
 use Config\App;
 use Config\Services;
+use Generator;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Group;
 use PHPUnit\Framework\ExpectationFailedException;
@@ -1828,18 +1829,26 @@ public function testRuleWithAsteriskToMultiDimensionalArray(): void
     }
 
     /**
+     * @param array<string, mixed>  $data
+     * @param array<string, string> $rules
+     * @param array<string, mixed>  $expectedData
+     *
      * @see https://github.com/codeigniter4/CodeIgniter4/issues/9219
      */
     #[DataProvider('provideMultipleAsterisk')]
-    public function testRuleWithMultipleAsterisk(array $data = [], array $rules = [], bool $expectedCheck = false, array $expectedData = []): void
-    {
+    public function testRuleWithMultipleAsterisk(
+        array $data = [],
+        array $rules = [],
+        bool $expectedCheck = false,
+        array $expectedData = []
+    ): void {
         $this->validation->setRules($rules);
 
         $this->assertSame($expectedCheck, $this->validation->run($data));
         $this->assertSame($expectedData, $this->validation->getValidated());
     }
 
-    public static function provideMultipleAsterisk(): iterable
+    public static function provideMultipleAsterisk(): Generator
     {
         yield 'success' => [
             [