Generic data sources

[a-ferri]

Issue-id

PR Checklist

---

• I have added example(s) inside the [./examples/] folder
• I have added the example(s) to the integration test list for normal (~30 minutes) or long runner >30 minutes
• I have checked the coding conventions as per the wiki
• I have checked to ensure there aren't other open Pull Requests for the same update/change?

Description

In complement to the PR caf-terraform-landingzones/pull/349 for caf-terraform-landingzones module, we need a new variable here.
It will also merge additional data into the combined_objects locals.

This change aims to permit us to query resources not managed by CAF module so we can reference them through landing zone keys - the same we do with resources managed by CAF module.

Please refer to this PR for more information.

Does this introduce a breaking change

• YES
• NO

Testing

[arnaudlh]

Like the concept, will validate and integrate :)

[LaurentLesle]

Thanks for the PR. Looks like a good way to reference existing object and reference them by their key