Remove build:ts step from npm start Task

[zoulou00]

[

Checklist

• [x] run npm run test
• [x] 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 ](https://github.com/fastify/fastify-cli/issues/705)

[mcollina]

Why?

[zoulou00]

To resolve the issue https://github.com/fastify/fastify-cli/issues/705 I thought this is what you wanted to do... sorry if it's not the case