[Possible regresion] Autoplan ignores when_modified in a per-repo config

[szaffarano]

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Overview of the Issue

We were able to reproduce this issue running v0.24.3, v0.24.4 and v0.25.0.

We have a project structure similar to

test
├── atlantis.yaml
└── infra
    ├── modules
    │   └── module-one
    ├── project-one
    └── project-two

and our atlantis.yaml file looks like

version: 3
projects:
  - &template
    name: template
    dir: template
    workflow: default
    autoplan:
      enabled: true
      when_modified:
        - "**/*.tf"
        - ".terraform.lock.hcl"

  - <<: *template
    name: infra/project-one
    dir: ./infra/project-one
    workflow: project-one

  - <<: *template
    name: infra/project-two
    dir: ./infra/project-two
    workflow: project-two

Atlantis is running with the following environment variables

ATLANTIS_AUTOPLAN_MODULES=true
ATLANTIS_AUTOPLAN_FILE_LIST=**/*.tf

Everything works as expected, i.e.,

1. We change project-one/main.tf and atlantis runs the plan just for project-one.
2. If we update modules/module-one/some-file.tf and module-one is used only for project-two, then Atlantis runs the plan only for project-two.
3. But if we change, for example, project-one/README.md Atlantis also runs the plan for project-one although the updated file doesn't match with ATLANTIS_AUTOPLAN_FILE_LIST.

If we downgrade to v0.23.3, the previous version after this fix, then use case 3) works (i.e., Atlantis doesn't run anything wen we change files not matching ATLANTIS_AUTOPLAN_FILE_LIST), but Autoplan Modules (use case 2) stops working. So, I'd say it's a regression introduced by the linked PR.

Reproduction Steps

Just follow the two use cases I listed above.

Logs

Environment details

Additional Context

[jamengual]

@jukie do you think this could be a bug?

[nipr-jdoenges]

Possible relation to #3368