v13.0.0

[p-zielinski]

• Added support for POST /v1/promotions/{campaignId}/tiers and PUT /v1/promotions/tiers/{promotionTierId}
• Added support for GET and POST /v1/rewards
• Added support for GET and PUT /v1/rewards/{rewardId}
• ❗❗❗ BREAKING CHANGES❗❗❗:
  • Property key of model Session in now String, not Enum.
  • Renamed model ValidationsRedeemableSkippedDetails -> ValidationsRedeemableSkippedResultDetails