querying by tx id fails

Describe the bug querying by tx id fails

To Reproduce Steps to reproduce the behavior:

let indexer_result = Indexer::new("https://algoindexer.testnet.algoexplorerapi.io/");
let indexer = indexer_result.unwrap();
let mut txn_query = QueryTransaction::default();
txn_query.txid = Some("Y5I4TYMKJI3MYJHBQ46DRHEXFW7BTURBKZ7V2NF2OU4QEHLYTKBQ".to_owned());
let txns_result = indexer.transactions(&txn_query).await;

gives an error trying to GET

https://algoindexer.testnet.algoexplorerapi.io/v2/transactions?tx-type=Y5I4TYMKJI3MYJHBQ46DRHEXFW7BTURBKZ7V2NF2OU4QEHLYTKBQ

which is asking for tx-type, whereas the code was filtering on txid.

Expected behavior

Screenshots If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

OS: [e.g. iOS]: macOS
Browser [e.g. chrome, safari]: chrome
Version [e.g. 22]:

Smartphone (please complete the following information):

Device: [e.g. iPhone6]
OS: [e.g. iOS8.1]
Browser [e.g. stock browser, safari]
Version [e.g. 22]

Additional context Add any other context about the problem here.

manuelmauro / algonaut

querying by tx id fails #204