Bump acorn from 5.7.3 to 5.7.4 (#562)
Bump acorn from 5.7.3 to 5.7.4 (#562)

Bumps [acorn](https://github.com/acornjs/acorn) from 5.7.3 to 5.7.4.
- [Release notes](https://github.com/acornjs/acorn/releases)
- [Commits](https://github.com/acornjs/acorn/compare/5.7.3...5.7.4)

Signed-off-by: dependabot[bot] <5bdcd3c0d4d24ae3e71b3b452a024c6324c7e4bb@github.com>

Co-authored-by: dependabot[bot] <1c358da00a777d4e9898c1280ab801e2df165188@users.noreply.github.com>
jupyterlab/jupyterlab-git,jupyterlab/jupyterlab-git,jupyterlab/jupyterlab-git