test: move debugger tests with --port=0 to parallel

Before

```
❯ tools/test.py "sequential/test-debugger*"
[00:25|% 100|+  32|-   0]: Done

All tests passed.
❯ tools/test.py -J "parallel/test-debugger*"
[00:05|% 100|+   6|-   0]: Done

All tests passed.
```

After

```
❯ tools/test.py "sequential/test-debugger*"
[00:06|% 100|+   5|-   0]: Done

All tests passed.
❯ tools/test.py -J "parallel/test-debugger*"
[00:05|% 100|+  33|-   0]: Done

All tests passed.
```

PR-URL: #47274
Refs: #47146
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
Reviewed-By: James M Snell <jasnell@gmail.com>

Author: joyeecheung