Consider to move @types/koa to devDependencies

[imballinst]

Hello! Thanks for creating this library, it's super helpful.

I have a question about this part:

koa2-swagger-ui/package.json

Lines 21 to 26 in a601b85

	"dependencies": {
	"@types/koa": "^2.13.9",
	"handlebars": "^4.7.8",
	"lodash": "^4.17.21",
	"read-pkg-up": "7.0.1"
	},

Would it make more sense to move it to devDependencies? Because dependencies are transitive dependencies, which are also installed when we install koa-swagger-ui, hence it may cause multiple copies of @types/koa. Maybe a good reference: https://issuu.com/johan.corrales.teams.test.1/docs/effective_typescript/s/16753105

Feel free to close if this is an invalid request, or if it doesn't make sense. Thanks!

[github-actions]

🎉 This issue has been resolved in version 5.10.0 🎉

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• npm package (@latest dist-tag)
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