Faster initialization

[gurgunday]

It doesn't amount to much, but I'm consistently seeing faster initialization results with a for loop instead of forEach. I tested the difference very simply by wrapping the whole plugin with console.time() and running the tests. With the for loop, the startup almost always takes less then 0.01ms, which otherwise does not happen on my machine

This PR also fixes a test, makes linting part of the test suite, adds the lint:fix script as well as @fastify/pre-commit

OLD

test/httpErrorsReply.test.js 1> default: 0.01ms
test/httpErrorsReply.test.js 1> default: 0.01ms
test/httpErrorsReply.test.js 1> default: 0.014ms
test/httpErrorsReply.test.js 1> default: 0.012ms
test/httpErrorsReply.test.js 1> default: 0.011ms
test/httpErrorsReply.test.js 1> default: 0.01ms
test/httpErrorsReply.test.js 1> default: 0.013ms
test/httpErrorsReply.test.js 1> default: 0.014ms
test/httpErrorsReply.test.js 1> default: 0.019ms
test/httpErrorsReply.test.js 1> default: 0.015ms
test/httpErrorsReply.test.js 1> default: 0.011ms
test/httpErrorsReply.test.js 1> default: 0.01ms
test/httpErrorsReply.test.js 1> default: 0.012ms
test/httpErrorsReply.test.js 1> default: 0.011ms
test/httpErrorsReply.test.js 1> default: 0.01ms
test/httpErrorsReply.test.js 1> default: 0.01ms
test/httpErrorsReply.test.js 1> default: 0.01ms
test/httpErrorsReply.test.js 1> default: 0.01ms
test/httpErrorsReply.test.js 1> default: 0.014ms
test/httpErrorsReply.test.js 1> default: 0.011ms
test/httpErrorsReply.test.js 1> default: 0.011ms
test/httpErrorsReply.test.js 1> default: 0.013ms
test/httpErrorsReply.test.js 1> default: 0.014ms
test/httpErrorsReply.test.js 1> default: 0.013ms
test/httpErrorsReply.test.js 1> default: 0.012ms

NEW

test/httpErrorsReply.test.js 1> default: 0.01ms
test/httpErrorsReply.test.js 1> default: 0.009ms
test/httpErrorsReply.test.js 1> default: 0.008ms
test/httpErrorsReply.test.js 1> default: 0.008ms
test/httpErrorsReply.test.js 1> default: 0.008ms
test/httpErrorsReply.test.js 1> default: 0.008ms
test/httpErrorsReply.test.js 1> default: 0.008ms
test/httpErrorsReply.test.js 1> default: 0.008ms
test/httpErrorsReply.test.js 1> default: 0.008ms
test/httpErrorsReply.test.js 1> default: 0.008ms
test/httpErrorsReply.test.js 1> default: 0.008ms
test/httpErrorsReply.test.js 1> default: 0.012ms
test/httpErrorsReply.test.js 1> default: 0.009ms
test/httpErrorsReply.test.js 1> default: 0.009ms
test/httpErrorsReply.test.js 1> default: 0.009ms
test/httpErrorsReply.test.js 1> default: 0.009ms
test/httpErrorsReply.test.js 1> default: 0.009ms

Checklist

• run npm run test and npm run benchmark
• tests and/or benchmarks are included
• documentation is changed or added
• commit message and code follows the Developer's Certification of Origin
  and the Code of conduct

[mcollina]

lgtm

[Uzlopak]

Yes. Always avoid forEach map and co.