feat: add env variable to skip binary download on npm install (#17627)

* feat: add env variable to skip binary download on npm install

* docs: add "Skip binary download" section to install tutorial

docs/tutorial/installation.md

@@ -97,6 +97,17 @@ a text file. A typical cache might look like this:
├── SHASUMS256.txt-1.8.2-beta.3
```

## Skip binary download
When installing the `electron` NPM package, it automatically downloads the electron binary.

This can sometimes be unnecessary, e.g. in a CI environment, when testing another component.

To prevent the binary from being downloaded when you install all npm dependencies you can set the environment variable `ELECTRON_SKIP_BINARY_DOWNLOAD`.
E.g.:
```sh
ELECTRON_SKIP_BINARY_DOWNLOAD=1 npm install
```

## Troubleshooting

When running `npm install electron`, some users occasionally encounter

npm/install.js

@@ -15,6 +15,10 @@ try {
  // do nothing
}

if (process.env.ELECTRON_SKIP_BINARY_DOWNLOAD) {
  process.exit(0)
}

var platformPath = getPlatformPath()

var electronPath = process.env.ELECTRON_OVERRIDE_DIST_PATH || path.join(__dirname, 'dist', platformPath)