Enhancement: make notarization process optionally asynchronous

Considering that some of us pay for CI minutes, potentially waiting for hours for notarization to succeed or simply time out could be not so good.

I'm wondering if there's a flow to notarize electron apps where you could package and sign the app, submit it for notarization and retrieve the submission ID from the json results

```
xcrun notarytool submit test-app.zip --output-format=json
{"message":"Successfully uploaded file","path":"...\/test-app.zip","id":""}
```

and then _somehow_ cache the results in some state, and then at a later time perhaps after a quick polling job succeeds, start a new CI job, restore said cache, and give electron/notarize (and in most use cases, electron-packager) the instructions to continue from a cache and just pick up where it left off now that the notarization is done.

The latter half of this plan sounds quite complex, but this is such a strange, asynchronous process that doesn't lend itself well to CI it seems.

Any thoughts?