fix code smell

Author: nefelhhh

application/src/main/java/org/togetherjava/tjbot/features/help/HelpThreadCommand.java

@@ -23,12 +23,7 @@
 
 import java.time.Instant;
 import java.time.temporal.ChronoUnit;
-import java.util.Arrays;
-import java.util.EnumMap;
-import java.util.Locale;
-import java.util.Map;
-import java.util.Objects;
-import java.util.Optional;
+import java.util.*;
 import java.util.concurrent.TimeUnit;
 import java.util.function.BiConsumer;
 import java.util.function.Function;
@@ -213,7 +208,7 @@ private void resetActivity(SlashCommandInteractionEvent event, ThreadChannel hel
 
         helpThread.getHistory()
             .retrievePast(1)
-            .map(messages -> messages.getFirst())
+            .map(List::getFirst)
             .queue(lastMessage -> manuallyResetChannelActivityCache.put(helpThread.getIdLong(),
                     lastMessage.getIdLong()));