USWDS-Site: Use node lts 20

[mejiaj]

Summary

Use latest LTS version of node. Update package dependencies and repo to use the latest LTS version of node. Prevents compatibility issues with cloud pages.

Related issue

Related to uswds/uswds#5010. Extension of #2304.

Preview link

Preview link [homepage]

Problem statement

To keep things up-to-date, secure, and functioning we need to update to latest node LTS version.

Solution

1. Use node 20
2. Update minor and patch deps.
3. Stay on Prettier 2x version (Updating to 3 causes issues with current linting. Will address in USWDS-Site: Replace gulp-eslint #2357)

Testing and review

1. No regressions in linting.
2. No regressions in compiling.
3. No regressions with npm install.

Dependency updates

Dependency name	Previous version	New version
@uswds/compile	1.0.0	1.1.0
chrome-remote-interface	0.31.0	0.33.0
concurrently	7.3.0	8.2.2
eslint-config-prettier	8.5.0	9.0.0 9.1.0
eslint-plugin-import	2.28.1	2.29.0 2.29.1
fancy-log	1.3.3	2.0.0
postcss	8.4.31	8.4.32
postcss-csso	5.0.1	6.0.1
prettier	2.4.1	2.8.8
sass	1.69.2	1.69.5
snyk	1.1234.0	1.1246.0 1.258.0 1.1264.0 1.1266.0
stylelint	15.10.3	15.11.0
axe-core	4.8.2	4.8.3

[mahoneycm]

New vulnerability

Running npm install added a new high rated vulnerability.

Luckily, npm audit fix cleared it up and restored 0 vulnerabilities to match main.

We should add that to this branch to limit vulnerabilities introduced

[mahoneycm]

Lgtm! Thanks for updating

[mejiaj]

HTMLProofer is failing because of new 18F URLs for guides. Opened issue in uswds/uswds#5683 because README content is being pulled on developer docs.

[mejiaj]

Blocked until USWDS - README: Update broken 18f links #5684 is merged. PR has been merged.