docs(recipes): add documentation recipe for testcontainers

[MacMacky]

PR Checklist

Please check if your PR fulfills the following requirements:

• The commit message follows our guidelines: https://github.com/nestjs/docs.nestjs.com/blob/master/CONTRIBUTING.md

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Docs
• Other... Please describe:

What is the current behavior?

Issue Number: #3122

What is the new behavior?

Adds a new Recipe for testing using Testcontainers

Does this PR introduce a breaking change?

• Yes
• No

Other information

[MacMacky]

@micalevisk bumping this one 🙏🏽 , pls let me know if you have any suggestions

[micalevisk]

I guess mentioning S3 and LocalStack are too specific to be under the testcontainer recipe... it seems that the whole process is more complex than it could be for projects that don't rely on AWS services directly.

I wonder if we can show here just enough for a basic nestjs+jest+testcontainer project, while also leaving room for others testing frameworks (as the docs already shows vitest stuff, for example).

[MacMacky]

okay, that makes sense, I appreciate the feedback here @micalevisk, I'll update the PR, putting this on draft for now, thanks