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