SelectButton broken in v16.7.0

[rosenthalj]

Describe the bug

The SelectButton doesn't work.

• property allowEmpty is ignored
  -- empty is incorrectly always allowed
• optionValue never updated

Listed below are two videos running the exact same code except for the version of PrimeNG. In the videos the top SelectButton has allowEmpty=false and the bottom SelectButton has allowEmpty=true.

BAD: The first video is v16.7.0 and demonstrates that the SelectButton doesn't work. Both SelectButtons show the exact same behavior and the optionValue for each SelectButton never changes.

SelectButtonPrimeNG16.7.0.mov

GOOD: The second video is v16.6.0 and demonstrates the SelectButton working properly.

SelectButtonPrimeNG16.6.0.mov

Environment

Mac and Windows

Reproducer

https://stackblitz.com/edit/uqd2gx

Angular version

16.x

PrimeNG version

16.7.0

Build / Runtime

Angular CLI App

Language

TypeScript

Node version (for AoT issues node --version)

18.18.1

Browser(s)

safari, chrome, firefox

Steps to reproduce the behavior

1. Run reproducer: https://stackblitz.com/edit/uqd2gx
2. Click select buttons
3. Incorrect: labels "value = false" and "value1 = false" never changes
4. Incorrect: top SelectButton allows empty

Expected behavior

1. Labels should change
2. When allowEmpty=true SelectButton should not allow empty "selections"

[rosenthalj]

I started to investigate a fix, but there were too many "accessibility" changes to SelectButton.ts for me to feel comfortable modifying the code. I noticed that the "unselectable" properly was added. This may (or may not) have contributed to the bug, but the documentation is very confusing. Please see the annotated screenshot listed below.