atlantis generate repo-config should support automatically generating when_merged configuration

[mfuhrmeisterDM]

Describe the Feature

Currently atlantis generate repo-config uses a predefined set of strings to put into the config key for when_modified for an atlantis project. This has one major downside: Atlantis just scans the component directory for changes files which does not include changed files /stacks. If you have only a config change in the stack folder atlantis does not recognize that it need to plan this project.

Expected Behavior

when_modified should be completely generated with all files under the component itself and corresponding files in /stack.

Use Case

Configuration change in /stacks folder

Describe Ideal Solution

see expected behaviour.

Alternatives Considered

No response

Additional Context

No response