sim: log the interaction about to be executed with INFO

I think this is useful to see, without having to drop down to DEBUG
and seeing all the other stuff.

simulator/runner/execution.rs

@@ -179,7 +179,7 @@ pub(crate) fn execute_interaction(
     interaction: &Interaction,
     stack: &mut Vec<ResultSet>,
 ) -> Result<ExecutionContinuation> {
-    tracing::trace!(
+    tracing::info!(
         "execute_interaction(connection_index={}, interaction={})",
         connection_index,
         interaction