fleetd #442: drop the unused java.util.List import

The new test never names List — only ListAppender, which has its own
import. An unused import is an IDE warning, and this repo treats
warnings as gates. No behaviour change: FleetdStartupReportTest still
runs 1 test, 0 failures, BUILD SUCCESS, 0 compile errors.

fleetd/src/test/java/dev/ltms/fleet/FleetdStartupReportTest.java

@@ -11,7 +11,6 @@ import org.slf4j.LoggerFactory;
 
 import java.nio.file.Files;
 import java.nio.file.Path;
-import java.util.List;
 
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;