Upgrade to node16 + stop using the "set-output" command

Hi there

Just raising this, as it does not look like there is already an issue for this, but I am getting two warnings in my actions that use `aci-deploy`:

```
Node.js 12 actions are deprecated. For more information see: https://github.blog/changelog/2022-09-22-github-actions-all-actions-will-begin-running-on-node16-instead-of-node12/. Please update the following actions to use Node.js 16: Azure/aci-deploy
```

```
The `set-output` command is deprecated and will be disabled soon. Please upgrade to using Environment Files. For more information see: https://github.blog/changelog/2022-10-11-github-actions-deprecating-save-state-and-set-output-commands/
```

It would be nice if someone could make sure `aci-deploy` is updated, to we can get rid of these warnings 😅

Thanks!