Update nodemon to remove malware

[jaredtbates]

Our corporate antivirus caught this- nodemon plus multiple downstream dependencies are updating due to a vulnerability in the dependency "event-stream". More info can be found here: dominictarr/event-stream#116 and https://blog.npmjs.org/post/180565383195/details-about-the-event-stream-incident.

[CLAassistant]

All committers have signed the CLA.

[brian-mann]

With the ^ already set, that means that patches would automatically be installed without needing to explicitly set the version in package.json, which makes this unnecessary, but I will still merge this regardless.

[brian-mann]

Released in 3.1.3.