Update Node version

[BSFishy]

We need to start working on updating the version of Node we use. The version of Node that we use is currently EOL. We need to work on updating to Node 18.15.0. There are potentially some blockers in the way of this. For example, currently Webpack 4 is blocking, as it doesn't support newer versions of Node. We will either need to update it or replace it before we're able to update Node.

[BSFishy]

This is blocked by Webpack 4. It doesn't support Node 18

[jmetev1]

seems like only thing to update is nvmrc.
package.json has "docker_image": "node:10" but i left that alone since no one else has been updating it