Setup logging transport in tests

Without a transport Winston will print annoying "Attempt to write logs
with no transports" warnings all over the place.  Setup a transport in
tests that cause logging to suppress this.

test/setup_logging.js

@@ -0,0 +1,15 @@
+import { ConsoleTransport, TerminalFormat, logger } from "@clusterio/lib";
+
+// Some integration tests may cause log events, import this file for such tests
+// to avoid getting the "Attempt to write logs with no transports" warning when
+// running tests individually.
+
+before(function() {
+	const silent = process.env.SILENT_TEST;
+
+	logger.add(new ConsoleTransport({
+		level: "info",
+		format: new TerminalFormat(),
+		filter: () => !silent,
+	}));
+});