Remove the last few mentions of tslint in documentation

[Delapouite]

I'm submitting a...

• [ ] Regression
• [ ] Bug report
• [ ] Feature request
• [x] Documentation issue or request (new chapter/page)
• [ ] Support request => Please do not submit support request here, instead post your question on Stack Overflow.

Current behavior

Hello!

While reading the documentation pages about the CLI, a few paragraphs still talk about tslint and its configuration files.

Here's an example taken from the page dealing with Monorepo :

https://docs.nestjs.com/cli/monorepo

Expected behavior

Tslint is now deprecated. Various tasks have been made codewise to support ESlint along the last months, like this one : https://github.com/nestjs/typescript-starter/issues/69

So, in order to help new-comers in the JS ecosystem and avoid confusion on which linting tool they should be use, I think we should remove the last remaining mention of tslint in the doc, and mention ESLint instead.

If you approve this transition, I could submit a PR to resolve this soon.

Thanks.

[kamilmysliwiec]

Would you like to create a PR for this?

[Delapouite]

Sure! Done.

[kamilmysliwiec]

Thanks! Let's track this here https://github.com/nestjs/docs.nestjs.com/pull/2006