This fixes:
```
D:\a\playwright\playwright\packages\playwright\lib\common\process.js:119
await processRunner.gracefullyClose().catch(() => {});
^
TypeError: Cannot read properties of undefined (reading 'gracefullyClose')
at gracefullyCloseAndExit (D:\a\playwright\playwright\packages\playwright\lib\common\process.js:119:23)
at process.<anonymous> (D:\a\playwright\playwright\packages\playwright\lib\common\process.js:81:11)
at process.emit (node:events:513:28)
at emit (node:internal/child_process:946:14)
at processTicksAndRejections (node:internal/process/task_queues:84:21)
```
from
[here](https://github.com/microsoft/playwright/actions/runs/6424299724/job/17444659548#step:7:2936).
`gracefullyCloseAndExit` gets called via `__stop__` and wants to use
`processRunner` var which gets created during `__init__`. So its
`undefined` when `__stop__` gets called.
ce928cd12f