fix jekyll typo

_posts/2023-07-13-parametric.md

@@ -59,7 +59,7 @@ public interface GenericThrower<T extends Throwable> {
 
 If we take the first class. We have a `ParametricClass` with one `ParameterType` name `T`.
 
-![{{ classA<T> | escape }}](/img/posts/2023-07-13-parametric/genParametric.png){: .img-fill }
+![{{ 'classA<T>' | escape }}](/img/posts/2023-07-13-parametric/genParametric.png){: .img-fill }
 
 For the second class, we have a class that extends a parametric class with one parameter named `String`.
 `String` here is a class.