fix: send transactions to all connected peers (#3239)

Description
---
 Send transactions to all connected peers as we do with block propagation

Motivation and Context
---
Alternative to #3211.

How Has This Been Tested?
---
Existing tests / single line code change

base_layer/core/src/mempool/service/service.rs

@@ -490,7 +490,7 @@ async fn handle_outbound_tx(
     exclude_peers: Vec<NodeId>,
 ) -> Result<(), MempoolServiceError> {
     let result = outbound_message_service
-        .propagate(
+        .flood(
             NodeDestination::Unknown,
             OutboundEncryption::ClearText,
             exclude_peers,