create kit metadata

[webern]

Description

When a kit is built, also create the metadata container that provides kit-metdata.json (or whatever we name it). The kit metadata file says what kits the current kit depends on. See design doc for more info.

TODO - prior to https://github.com/bottlerocket-os/twoliter/issues/4 it is unclear whether the responsibility for this will be in twoliter or buildsys. Move this issue or create a Bottlerocket issue if it becomes the responsibility of buildsys.

Definition of Done

When building a kit also creates a metadata container with a JSON file in it describing the kit's dependencies.

Depends on:

• [ ] https://github.com/bottlerocket-os/twoliter/issues/4
• [ ] https://github.com/bottlerocket-os/bottlerocket/issues/3217

id: kitmeta
epic: kits

Related to https://github.com/bottlerocket-os/bottlerocket/issues/2669