Add org-slug and org-id flags to orb validate & process commands

[zbenhadi]

Checklist

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• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have checked for similar issues and haven't found anything relevant.
• This is not a security issue (which should be reported here: https://circleci.com/security/)
• I have read Contribution Guidelines.

Internal Checklist

• I am requesting a review from my own team as well as the owning team
• I have a plan in place for the monitoring of the changes that I am making (this can include new monitors, logs to be aware of, etc...)

Changes

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• Added a new orbOrgOptions struct, to represent org-slug and org-id values
• Added a new api package: collaborators - presents an interface with a single method "GetOrgCollaborations"
• Changed "ValidateOrb" GQLQuery to include "ownerId" param, based on org-slug and org-id flags

Rationale

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Integrate the capability to validate an orb when using other private orbs from the same namespace.

[JulesFaucherre]

It seems the usage ask to use the <vcs-name>/<org-name> but the code only supports the <vcs-short>/<org-name> syntax

[JulesFaucherre]

Very great job, thanks for also fixing the slug issue on config validate!