TreeSelect: panelClass not working

[xchimera]

Describe the bug

It seems that the panelClass attribute is not being used. I expect that the class i set in the panelClass is a class that is being set on https://github.com/primefaces/primeng/blob/805d88b385f5fe606af591a6e8e6f5ea8107da65/src/app/components/treeselect/treeselect.ts#L49
In the latest version for angular 13 (primeng 13.4.1) that is not the case, as seems evident in treeselect.cs

Environment

angular 13.3.11
PrimeNG 13.4.1

Reproducer

https://stackblitz.com/edit/github-wjckhs?file=src/app/app.component.html

Angular version

13.3.11

PrimeNG version

13.4.1

Build / Runtime

Angular CLI App

Language

TypeScript

Node version (for AoT issues node --version)

16.15.1

Browser(s)

No response

Steps to reproduce the behavior

Add a p-treeSelect and add a panelClass property. In DevTools it can be seen that this class is never attached to the element. Looking at the source code it is unused

Expected behavior

That the opened panel has the class attached

[xchimera]

Awesome with a quick fix. Is it possible to create a 13.4.2 with this patch?