Simplify collection initialization

QuadtreeTests/Tests.cs

@@ -43,7 +43,7 @@ namespace QuadtreeTests
         public void TestQuery()
         {
             AddEntitiesAndAssertCount();
-            List<TestEntity> result = new();
+            List<TestEntity> result = [];
             _quadtree.Query(new Rectangle(new Vector2(2.5f, 2.5f), new Vector2(10.0f, 10.0f)), result);
             Assert.That(result, Has.Count.EqualTo(2));
         }