Summary:
`webpack-dev-server` depends on `selfsigned` which depends on a version of `node-forge`
with a security bug. This forces an upgrade on `selfsigned` to patch the vuln.

Test Plan: Running the UI still works.

Reviewers: zasgar, michelle, nick, #engineering

Reviewed By: zasgar, #engineering

Differential Revision: https://phab.corp.pixielabs.ai/D6680

GitOrigin-RevId: 0ac05856379fbc23ef8505d602449b69eb2b89c0