method FSWatcher.ref
Usage in Deno
```typescript import { type FSWatcher } from "node:node__fs.d.ts"; ```
FSWatcher.ref(): this
When called, requests that the Node.js event loop _not_ exit so long as the `fs.FSWatcher` is active. Calling `watcher.ref()` multiple times will have
no effect.
By default, all `fs.FSWatcher` objects are "ref'ed", making it normally
unnecessary to call `watcher.ref()` unless `watcher.unref()` had been
called previously.
this