Update testdox for remaining unit tests

tests/unit/Mapper/CountMapperTest.php

@@ -18,6 +18,7 @@ use PHPUnit\Framework\TestCase;
 #[TestDox('Count Mapper (Unit tests)')]
 class CountMapperTest extends TestCase
 {
+    #[TestDox('map() succeeds')]
     public function testMapSucceeds(): void
     {
         $this->assertEquals(5, (new CountMapper())->map([5, 8, 10]), 'Count not correct');