v3.1.0

📚 PR:

• Bump fastify-plugin from 2.3.4 to 3.0.0
• Bump standard from 14.3.4 to 15.0.0
• Bump snazzy from 8.0.0 to 9.0.0
• Bump standard from 15.0.1 to 16.0.2
• fix lint
• feat: add stale (#22)
• chore: add dependabot automerge (#28)
• test: 100% coverage (#29)
• feat: cache (#31)