incorrect test in TestJob_ComplicatedTransfer silently failing

[0rphon]

Describe the bug
I've been going through the constructor code and it seems like the following action is being populated incorrectly and then silently failing to unmarshal.
https://github.com/coinbase/rosetta-sdk-go/blob/255864dbd02229a03b9d1f209ba112bd59c26211/constructor/worker/worker_test.go#L1012-L1015

To Reproduce
if you put println(types.PrettyPrintStruct(input)) after this block you'll see that it fails to unmarshal the KeyPair but never throws an error.
https://github.com/coinbase/rosetta-sdk-go/blob/255864dbd02229a03b9d1f209ba112bd59c26211/constructor/worker/worker.go#L258-L262

Expected behavior
seeing how this is meant to be a valid test, im assuming everything inside it should unmarshal correctly. and seeing how you have tests to reject invalid json, this should probably be throwing an error too.

Additional context
the actions input after populate_input mutates it:

{"account_identifier": {"address":"test"}, "keypair": {"hex_bytes":"02418b0f5ab5f72219a84ac80704504dbb3c221c2d4f0065c7e4ca93618c472ad7","curve_type":"secp256k1"}}

and the result of its unmarshalling inside the SaveAccountWorker method:

{
 "account_identifier": {
  "address": "test"
 },
 "keypair": {
  "private_key": "",
  "public_key": null
 }
}