Consider posting the platform-specific for `grpc-tools` binaries to npm

### Is your feature request related to a problem? Please describe.
`grpc-tools` uses `node-pre-gyp` to fetch platform-specific binaries at install time.
In build environments with an outbound-traffic allow-list this download phase fails, blocking CI/CD pipelines.

#### Environment
* Private build agents behind a strict firewall
* Only a few hosts (such as internal artifact feeds) are reachable

#### Current behaviour
```text
.../node_modules/grpc-tools install: node-pre-gyp http GET https://node-precompiled-binaries.grpc.io/grpc-tools/v1.13.0/linux-x64.tar.gz
.../node_modules/grpc-tools install: node-pre-gyp ERR! install request to https://node-precompiled-binaries.grpc.io/grpc-tools/v1.13.0/linux-x64.tar.gz failed, reason: Client network socket disconnected before secure TLS connection was established
```

### Describe the solution you'd like
Could you provide an installation path that works without any additional endpoints?
For example, ship the binaries in the package or as separate npm packages.