Bump firebase from 12.14.0 to 12.15.0

Bumps [firebase](https://github.com/firebase/firebase-js-sdk) from 12.14.0 to 12.15.0.
- [Release notes](https://github.com/firebase/firebase-js-sdk/releases)
- [Changelog](https://github.com/firebase/firebase-js-sdk/blob/main/CHANGELOG.md)
- [Commits](https://github.com/firebase/firebase-js-sdk/compare/firebase@12.14.0...firebase@12.15.0)

---
updated-dependencies:
- dependency-name: firebase
  dependency-version: 12.15.0
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

package.json

@@ -20,7 +20,7 @@
     "@discordjs/voice": "^0.19.2",
     "@discordjs/opus": "^0.10.0",
     "dotenv": "^17.4.2",
-    "firebase": "^12.14.0",
+    "firebase": "^12.15.0",
     "firebase-admin": "^14.0.0",
     "he": "^1.2.0",
     "ms": "^2.1.3",