v0.4.0

## Main change - update front end to React 18 (mostly complete) and build agent to Node 18

What's Changed

• Combined PR by @github-actions in #48
• Bump @types/jest from 29.1.1 to 29.1.2 in /frontend by @dependabot in #38
• Bump pyfakefs from 4.7.0 to 5.0.0 by @dependabot in #45
• Bump eslint from 8.24.0 to 8.25.0 in /frontend by @dependabot in #37
• Bump react-router-dom from 6.4.0 to 6.4.2 in /frontend by @dependabot in #40
• Bump @typescript-eslint/parser from 5.38.0 to 5.39.0 in /frontend by @dependabot in #41
• Bump @babel/preset-env from 7.19.1 to 7.19.3 in /frontend by @dependabot in #43
• [Snyk] Upgrade: react, react-dom by @snyk-bot in #46
• Combined PR by @github-actions in #49
• Bump whitenoise from 6.0.0 to 6.2.0 by @dependabot in #44
• [Snyk] Upgrade react-router-dom from 6.4.0 to 6.4.1 by @snyk-bot in #47
• Update frontend to React 18 and update build engine to Node 18 by @mnbf9rca in #50

Full Changelog: 0.3.0...0.4.0