Use node version matching production.

[jtorreggiani]

PR Overview

Updating the .nvmrc file to include a version of node that matches what is used in production.

Type of contribution

• Code
• Documentation

Reference: Issue or Pull Request (PR)

• Towards Contributing: how to interpret the npm warnings? #402

Description of Changes

We want to make sure we are using the same node version that is used in production. This will help avoid BAD_ENGINE errors.

Before and After for UI Updates

N/A

For PR Reviewer

• Does this file change the yarn.lock, package.json or package-lock.json file? If so, why?
• If this pr contains mobile and desktop changes, did you test on IphoneXr and desktop views?
• Does this file match the related tickets linked figma file, or does it pass the visual smell test?
• If this file contains javascript, does the javascript pass the smell test?
• If you don't feel super confident in your review, did you assign someone more senior to double check?