Parallel "--by pool" not working, hanging and spamming startup banner

We have historically suffered from idle workers due to the wide range of test duration, so when I saw the `--by pool` mode I thought we'd be able to speed up our tests for free basically ;) (ref: https://codecept.io/parallel/#dynamic-test-pooling-mode)

But it seems to not be working as expected. A couple of issues I noticed:

1. When I run with pool mode it seems to just hang after a certain amount of time without any clear reason why.

We're using Puppeteer, and my suspicion is that the browser's WebSocket connection keeps the Node event loop alive in the worker thread after the port is closed, so the parent never sees the worker exit and _finishRun() never gets called.

2. Also, the startup message is fired every time a worker takes a test, so the output gets absolutely hammered which is not ideal for CI

e.g. (example output)
```
CodeceptJS v3.7.7 #StandWithUkraine
Running tests in 1 workers...

CodeceptJS v3.7.7 #StandWithUkraine
Using test root "/home/user/project"

Login suite --
[Worker 01] ✔ Login suite › User can log in in 3401ms
✔ User can log in in 3401ms

OK | 1 passed // 4s
CodeceptJS v3.7.7 #StandWithUkraine
Using test root "/home/user/project"

Login suite --
[Worker 01] ✔ Login suite › User sees error on bad credentials in 2980ms
✔ User sees error on bad credentials in 2980ms

OK | 2 passed // 8s
CodeceptJS v3.7.7 #StandWithUkraine
Using test root "/home/user/project"
...

Inizia con la modalità dinamica di pooling dei test descritta nella documentazione collegata e traccia il ciclo di vita dei worker intorno a _finishRun(). Riproduci il blocco con Puppeteer e verifica che i worker terminino correttamente e che il banner di avvio venga emesso una sola volta, anziché per ogni assegnazione di test.

Scritto dal modello di indicizzazione a partire dal testo della issue.