Add a branch REST Endpoints

Designer/Branch APIs/Add a branch
The operations from the Designer/Branch APIs/Add a branch category.
[Deprecated]: V1.0
Method: post
Path: /ec-designer-svc/rest/v1.0/studies/{studyId}/versions/{version}/branches
V2.0
Method: post
Path: /ec-designer-svc/rest/v2.0/studies/{studyId}/versions/{version}/branches