Add npm shim for `safer-buffer`

### Describe the feature

[`safer-buffer`](https://www.npmjs.com/package/safer-buffer) used by `mysql2`

```
mysql2 3.13.0
└─┬ iconv-lite 0.6.3
  └── safer-buffer 2.1.2
```

it breaks compatibility with cloudflare 

### Additional information

- [ ] Would you be willing to help implement this feature?