Project-factory: allow folder_id to be defined in defaults_file

[Malet]

Currently, setting the folder_id in defaults.yaml but not in the project.yaml, results in:

╷
│ Error: Unsupported attribute
│ 
│   on main.tf line 44, in module "projects":
│   44:   folder_id              = each.value.folder_id
│     ├────────────────
│     │ each.value is object with 1 attribute "labels"
│ 
│ This object does not have an attribute named "folder_id".
╵

This change allows you to set the folder_id in the defaults.yaml and have it be used for all the projects selected by the glob pattern.

[juliocc]

Thanks @Malet!