"Ignoring unsupported arg:" lines in emulator launch logs

### [REQUIRED] Environment info

- `firebase-tools` 11.3.0
- Platform: Cloud Build (Alpine Linux image)

### [REQUIRED] Test case

No minimum reproducible. Let me explain..

When debugging my CI scripts, I found that Firebase Emulators log some concerning lines.

```
Step #3: [debug] [2022-07-19T08:29:52.780Z] Ignoring unsupported arg: projectId {"metadata":{"emulator":{"name":"database"},"message":"Ignoring unsupported arg: projectId"}}
Step #3: [debug] [2022-07-19T08:29:52.780Z] Ignoring unsupported arg: auto_download {"metadata":{"emulator":{"name":"database"},"message":"Ignoring unsupported arg: auto_download"}}
Step #3: [debug] [2022-07-19T08:29:52.781Z] Ignoring unsupported arg: rules {"metadata":{"emulator":{"name":"database"},"message":"Ignoring unsupported arg: rules"}}
```

Why this matters? I thought I'm doing something wrong here (so this serves as confusion to us developers). I am not. Somewhere internally, Firebase Emulators call the Realtime Database emulator in a wrong way. This may be an indication of a bug, but at the least, I'd like such lines to be ironed out from us.

### [REQUIRED] Expected behavior

Firebase Emulators would give such warnings only if my code is doing something wrong.

### [REQUIRED] Actual behavior

Warnings I have nothing to do show up.

### Steps to reproduce

Launch Emulators on a project that at least has Realtime Database.

```
$ firebase emulators:start --project=demo-2
```

Observe `database-debug.log` after the emulators have been launched.