Finds and updates an existing transaction, provided valid search criteria is passed.

• 'find_with': does a search on each key/value pair
• 'ignore_if'. will not update if any of the dictionary items match key value pair for the value you can put null, 'null', 'not null' or an actual value
• 'overwrite_if_null': will overwrite the value ONLY if it is NULL on Sisu side
• 'ignore_inbound_null' will ignore any inbound NULL values (if True)
• 'create_if_needed': will create the record if it is not found
• return_fields: (array) will return specific fields. 'pipeline_status' and 'external_guids' are NOT client fields, but can be specified
• 'client_id' will ALWAYS be returned