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.