Connect to Firebase Storage Emulator?

### [READ] Step 1: Are you in the right place?

* For issues or feature requests related to __the code in this repository__
file a Github issue.
* If this is a __feature request__ make sure the issue title starts with "FR:".
* For general technical questions, post a question on [StackOverflow](http://stackoverflow.com/)
with the firebase tag.
* For general Firebase discussion, use the [firebase-talk](https://groups.google.com/forum/#!forum/firebase-talk)
google group.
* For help troubleshooting your application that does not fall under one
of the above categories, reach out to the personalized
[Firebase support channel](https://firebase.google.com/support/).

### [REQUIRED] Step 2: Describe your environment

* Operating System version: MacOS 10.15.7
* Firebase SDK version: latest
* Library version: 7.3.0
* Firebase Product: Storage

### [REQUIRED] Step 3: Describe the problem

I'm using this library and I'm trying to use the environment variable `FIREBASE_STORAGE_EMULATOR_HOST` to get it to point to the local emulator that I'm running. It doesn't seem to work. However, when I search for `FIREBASE_STORAGE_EMULATOR_HOST` in this project, I can't seem to find it either. The documentation lead me to believe that I can manipulate the SDK to use the emulator by setting this environment variable, but that doesn't seem to be the case for Java.

1. Can someone confirm this?
2. How should I be connecting my development server to the storage emulator? I detail how I tried to use the google cloud storage sdk to do that and failed here: https://github.com/googleapis/java-storage/issues/875