Invalid error responses in `get_transaction`

First query to hived:

curl -s -H 'Content-Type: application/json' -d {"id":1,"jsonrpc":"2.0","method":"account_history_api.get_transaction","params":{"id":"100"}}' https://api.hive.blog

returns with following message:

Assert Exception:false: Unknown Transaction 1000000000000000000000000000000000000000

in python HAfAH:

unknown SQL exception

and in postgREST:

invalid hexadecimal data: odd number of digits

so both are incorrect, but in postgREST theere is also invalid return code (400 instead of 200)

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Second query for hived:

curl -s -H 'Content-Type: application/json' -d {"id":1,"jsonrpc":"2.0","method":"account_history_api.get_transaction","params":{"id":"zxzxz"}}' https://api.hive.blog

got response:

unspecified:Invalid hex character 'z'

in python HAfAH:

unknown SQL exception

and in postgREST:

invalid hexadecimal digit: \"z\"

and same as before in case of postgREST, there is invalid status code

@kristupas