Modify already done transaction

As an admin, I want to be able to modify an already done transaction so that I could fix any mistakes made by the users

Acceptance criteria

There exists an endpoint POST /api/v1/accounts/transactions/{id} where the id stands for an already existing transaction id. This endpoint takes the requestbody for a new transaction. Instead of updating an already existing transaction, we instead make a new one.

So let's say transaction1 was A transferring 50 euros to B. We want to modify this so that A actually transfers 20 euros. To do this, we make a new transfer where B transfers 30 euros to A.