Retrieve a vesting start transaction contract and return it as an OCF JSON object.
The LedgerJsonApiClient instance
Parameters containing the contract ID
The vesting start data in OCF format along with the contract ID
https://schema.opencaptablecoalition.com/v/1.2.0/objects/transactions/vesting/VestingStart.schema.json
Retrieve a vesting start transaction contract and return it as an OCF JSON object.