Bump lodash from 4.17.11 to 4.17.21 in /cloudfunctions/cloud_class

Bumps [lodash](https://github.com/lodash/lodash) from 4.17.11 to 4.17.21.
- [Release notes](https://github.com/lodash/lodash/releases)
- [Commits](lodash/lodash@4.17.11...4.17.21)

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