Configure onlyBuiltDependencies for pnpm

[neonbyte1]

pnpm triggers a warning when you're installing the dependencies, which can be avoided by configuring pnpm.onlyBuiltDependencies via package.json.

╭ Warning ───────────────────────────────────────────────────────────────────────────────────╮
│                                                                                            │
│   Ignored build scripts: @nestjs/core, @swc/core.                                          │
│   Run "pnpm approve-builds" to pick which dependencies should be allowed to run scripts.   │
│                                                                                            │
╰────────────────────────────────────────────────────────────────────────────────────────────╯