[karma-server]: TypeError: Cannot read property 'range' of undefined - Angular Unit Testing in CI environment

Was able to figure it out. We were using node:latest in our .gitlab-ci.yml file and whatever that was pulling down was causing an issue. (It looked to be version 15). So instead of node:latest, we set it to node:14.

It's indeed an issue with karma on node v15. Looks like (for now) it will not be fixed, so downgrading to v14 is the solution: https://github.com/karma-runner/karma/issues/3571