Ensure calling signTransaction uses the returned Transaction (#440)

Author: lorisleiva

.changeset/sixty-moons-eat.md

@@ -0,0 +1,5 @@
+---
+'@metaplex-foundation/js': patch
+---
+
+Ensure calling signTransaction uses the returned Transaction

packages/js/src/plugins/rpcModule/RpcClient.ts

@@ -95,7 +95,7 @@ export class RpcClient {
 
     // Identity signers.
     for (let i = 0; i < identities.length; i++) {
-      await identities[i].signTransaction(transaction);
+      transaction = await identities[i].signTransaction(transaction);
     }
 
     return transaction;