v4.0.1

📚 PR:

• Bump form-data from 3.0.1 to 4.0.0
• Merge pull request #199 from fastify/dependabot/npm_and_yarn/form-data-4.0.0
• chore(gitignore): use latest github ignore template (#203)
• chore: include os name in build name (#205)
• ci(dependabot): update github actions (#206)
• Bump fastify/github-action-merge-dependabot from v1 to v1.2.1 (#209)
• Bump actions/setup-node from v1 to v2.1.5 (#208)
• feat: req.file throws filesize error (#207)
• Feature/increase test coverage (#204)
• Fix test failures (#210)