Update to latest Node LTS

[thisisdano]

Is your feature request related to a problem? Please describe.

USWDS tries to stay at the current Node LTS, which is currently 18.12.2 18.18.1. Our nvmrc file pins us to Node 16.

Describe the solution you'd like

Let's update to the current LTS (18.12.2 18.18.1) and update our nvmrc and our CI settings to match, for both the uswds and uswds-site repos at first. But each of our repos should use the current LTS.

Describe alternatives you've considered

These isn't a problem with the current setup, so an alternative is to do nothing

Additional context

No response

Code of Conduct

• I agree to follow this project's Code of Conduct.
• I checked the current issues for duplicate feature requests.

[thisisdano]

I'm going to mark this as blocked since current Storybook uses Webpack 4 and Webpack 4 does not support Node 17 and higher. We'll need to wait until we can build with Storybook 7 and Webpack 5 to make this upgrade. Since there doesn't seem to be any compelling reason to upgrade to the most recent LTS, we'll just revisit later.

Source: storybookjs/storybook#19692

[mejiaj]

We need to schedule this due to Cloud Pages dropping support for Node 16 - cloud-gov/pages-build-container#437.

Semi-related to #5239.