Flank Scripts 1.9.0

feat: Added reading service account in Github action (#1663)

Fixes #1597

## Test Plan
> How do we know the code works?

### Flank scripts part
Run command
- `flankScripts firebase save_service_account --account=<file content, link, file path>` -> to test storing service account

### Github action part
You could run Flank GitHub action on [testing repository](https://github.com/Flank/flank-github-action-testing/actions)

## Checklist

- [x] Documented
- [x] Unit tested
- [x] Test repository updated