feat: add support for user-configured labels

[the-wondersmith]

PR adds support for applying user-configured labels to containers started by testcontainers.

Note

This PR is a precursor to future support of reusable containers

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[DDtKey]

Thank you a lot for the contribution! 🙏

I find this pretty small and simple PR looking good to me, just a few comments to discuss and LGTM! ✅

[the-wondersmith]

Thank you a lot for the contribution! 🙏

Absolutely my pleasure 😁

I find this pretty small and simple PR looking good to me, just a few comments to discuss and LGTM! ✅

I replied to both comments, and pushed the suggested changes. If the responses (and changes) make sense and to you look good, I'll leave the Resolve Conversation button to your discretion 😅

[DDtKey]

Perfect, LGTM ✅

I'll take a look at the second PR soon, thanks one more time! ❤️