fix: Change the default test log level to warn

zebra-test/src/lib.rs

@@ -10,8 +10,9 @@ static INIT: Once = Once::new();
 pub fn init() {
     INIT.call_once(|| {
         let fmt_layer = fmt::layer().with_target(false);
+        // Use the RUST_LOG env var, or 'warn' by default
         let filter_layer = EnvFilter::try_from_default_env()
-            .or_else(|_| EnvFilter::try_new("info"))
+            .or_else(|_| EnvFilter::try_new("warn"))
             .unwrap();
 
         tracing_subscriber::registry()