Firebase Rules Deploy may not deploy rules when project has multiple databases

### [REQUIRED] Environment info

15.3.1 (local dev build: [40df2d6](https://github.com/firebase/firebase-tools/commit/40df2d6abd352870acbff03c00d79e1e95185085))

**firebase-tools:**

**Platform:**
Linux (Debian)

### [REQUIRED] Test case

See #7981, it's a similar problem.

### [REQUIRED] Steps to reproduce
Prerequisites: multiple databases
```
# Download existing rules
firebase init firestore
# TODO: Modify the rules to those of another database
# Deploy the rules
firebase deploy --only 'firestore:d:rules' --debug
# You may see `latest version of firestore.rules already up to date, skipping upload...`.
```

### [REQUIRED] Expected behavior

The modified rules are deployed

### [REQUIRED] Actual behavior
The modified rules _may_ be skipped

### Details
As noted above, similar to #7981, we are using `getLatestRulesetName()` to get the rules, which does not filter by database and so is indeterministic about which rules it actually downloads.