change: [M3-8425, M3-8231] - Update TypeScript and Vitest

[bnussman-akamai]

Description 📝

• Updates TypeScript and Vitest 📦
• Remove npm-run-all and postinstall because we don't use them 🗑️
• I wanted to update just Typescript initially, but I was having issues getting Vitest's types to play nicely so I'm just going to give this a shot and see what happens

How to test 🧪

• Test local development
• Test production build (checking an internal preview link is sufficient)
• Verify Storybook still works locally
• Verify type-checking passes in GitHub Actions
• Verify Storybook builds in GitHub Actions for all packages
• Verify unit tests pass in GitHub Actions for all packages

As an Author I have considered 🤔

• [ ] 👀 Doing a self review
• [ ] ❔ Our contribution guidelines
• [ ] 🤏 Splitting feature into small PRs
• [ ] ➕ Adding a changeset
• [ ] 🧪 Providing/Improving test coverage
• [ ] 🔐 Removing all sensitive information from the code and PR description
• [ ] 🚩 Using a feature flag to protect the release
• [ ] 👣 Providing comprehensive reproduction steps
• [ ] 📑 Providing or updating our documentation
• [ ] 🕛 Scheduling a pair reviewing session
• [ ] 📱 Providing mobile support
• [ ] ♿ Providing accessibility support

[github-actions[bot]]

Coverage Report: ✅
Base Coverage: 82.73%
Current Coverage: 85.96%