fab add may not be idempotent

[mtarng]

Describe the bug:
When calling fab add it excludes type: component at the top level of the component.yaml.
Subsequently, if you run the same command again, type:component will be added as, I suspect, it's being added to the object when loading from the component.yaml file.

To Reproduce:

• Run fab add someservice --path ./someservice --method local --type component
• cat component.yaml:

  name: somepath
  subcomponents:
  - name: someservice
    type: component
    method: local
    path: ./someservice
  

• rerun fab add someservice --path ./someservice --method local --type component
• cat component.yaml:

  name: somepath
  type: component
  subcomponents:
  - name: someservice
    type: component
    method: local
    path: ./someservice
  

notice type: component has been added at the top level.
Expected behavior:
type: component should probably be added on the first run.

Screenshots:

Additional context:

Desktop (please complete the following information):

• OS:
  macOS
  Additional context

[andrewDoing]

I reproduced this bug on Windows.
The bug occurs within the function LoadComponent() in component.go

1st run: the error os.PathError is returned from UnmarshalComponent("yaml", ...)
loadedComponents and the error message "Error loading component in path ./" are returned.

2nd run: There is no error, as component.yaml now exists in the current directory. Moving forward, the function applyDefaultsAndMigrations() is called, adding the ComponentType of "component".

Potential Solution: Handle the specific error of os.PathError, adding the ComponentType of "component" in this case.