Add Variants to Experiment

[dsilvam]

• [x] Create variant:

  POST /experiments/{id}/variants (name will be autogenerated)
  

  Create variant with weight based on previous variations created and based on the spit method (evenly or custom percentage). This needs to update the trafficProportion object of the Experiment.

  Relate variant to experiment

• [x] Delete variant - DELETE /experiments/{id}/variants/{key}

Acceptance criteria:

• Everything included above
• Postman tests

[dsilvam]

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