build: Update actions-setup and move to tsx

[michaeltaranto]

Upgrading the pnpm/action-setup GitHub action to move CI from node v12 to v16.

Other updates include:

• Switching ts-node over to tsx as the runner for TypeScript scripts.
• Updating @manypkg/cli to fix pnpm issue in CI

[changeset-bot[bot]]

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Latest commit: 3b5bb91ba83425dc20a1303f78014f11eac6c36c

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