tests: fix npm vulnerabilities

A fresh v3.2 install reports the following during ``./bootstrap.sh``. Start with high severity.

```
found 8 vulnerabilities (1 low, 4 moderate, 3 high)
run `npm audit fix` to fix them, or `npm audit` for details
```

Start by running ./bootstrap.sh on a fresh v3.2 install and then inspect the npm audit output, prioritizing the three high-severity findings. Identify the dependency changes required and rerun the bootstrap and audit checks; done means the reported high-severity vulnerabilities are resolved.

Written by the indexing model from the issue text.