Bump firebase from 7.8.0 to 7.8.1

Bumps [firebase](https://github.com/firebase/firebase-js-sdk) from 7.8.0 to 7.8.1.
- [Release notes](https://github.com/firebase/firebase-js-sdk/releases)
- [Commits](https://github.com/firebase/firebase-js-sdk/compare/[email protected]@7.8.1)

Signed-off-by: dependabot-preview[bot] <[email protected]>

Author: dependabot-preview[bot]