related_transactions in the SearchTransactionsResponse of Rosetta vs. MinaMesh

[piotr-iohk]

When working on /search/transactions I've noticed that there is a difference in how empty related_transactions is presented in SearchTransactionsResponse in Rosetta vs. MinaMesh. In Rosetta empty related_transactions field is presented as:

"related_transactions": [],

In MinaMesh, in case of related_transactions: None the related_transactions is not serialized into the response at all.

RelatedTransaction is part of Transaction type, which is part of SearchTransactionsResponse. I suppose if we wanted to have the same behaviour we would need to serialize it to empty array when None via custom serialization behavior in https://github.com/harrysolovay/coinbase-mesh/blob/main/src/models/transaction.rs#L21.