checkstyle: enforce no whitespace at end of line

checkstyle.xml

@@ -40,6 +40,11 @@
 			<property name="message" value="Indent must use tab characters"/>
 			<property name="ignoreComments" value="true"/>
 		</module>
+		<module name="RegexpSinglelineJava">
+			<property name="format" value="[^\s]\s+$"/>
+			<property name="message" value="No trailing whitespace"/>
+			<property name="ignoreComments" value="true"/>
+		</module>
 		<module name="WhitespaceAround"/>
 		<module name="WhitespaceAfter">
 			<property name="tokens" value="COMMA"/>

runelite-client/src/main/java/net/runelite/client/plugins/grounditems/GroundItemsConfig.java

@@ -124,9 +124,9 @@ public interface GroundItemsConfig extends Config
 		description = "Configures whether or not to highlight tiles containing ground items",
 		position = 6
 	)
-	default boolean highlightTiles() 
-	{ 
-		return false; 
+	default boolean highlightTiles()
+	{
+		return false;
 	}
 
 	@ConfigItem(

runelite-client/src/main/java/net/runelite/client/plugins/itemprices/ItemPricesOverlay.java

@@ -152,9 +152,9 @@ class ItemPricesOverlay extends Overlay
 		ItemContainer container = null;
 
 		// Inventory item
-		if (widgetId == INVENTORY_ITEM_WIDGETID || 
-			widgetId == BANK_INVENTORY_ITEM_WIDGETID || 
-			widgetId == EXPLORERS_RING_ITEM_WIDGETID || 
+		if (widgetId == INVENTORY_ITEM_WIDGETID ||
+			widgetId == BANK_INVENTORY_ITEM_WIDGETID ||
+			widgetId == EXPLORERS_RING_ITEM_WIDGETID ||
 			widgetId == SEED_VAULT_INVENTORY_ITEM_WIDGETID)
 		{
 			container = client.getItemContainer(InventoryID.INVENTORY);

runelite-client/src/main/java/net/runelite/client/plugins/menuentryswapper/MenuEntrySwapperConfig.java

@@ -417,7 +417,7 @@ public interface MenuEntrySwapperConfig extends Config
 		name = "Essence Mine Teleport",
 		description = "Swaps Talk-To with Teleport for NPCs which teleport you to the essence mine"
 	)
-	default boolean swapEssenceMineTeleport() 
+	default boolean swapEssenceMineTeleport()
 	{
 		return false;
 	}

runelite-client/src/main/java/net/runelite/client/util/LinkBrowser.java

@@ -52,7 +52,7 @@ public class LinkBrowser
 	 */
 	public static void browse(final String url)
 	{
-		new Thread(() -> 
+		new Thread(() ->
 		{
 			if (Strings.isNullOrEmpty(url))
 			{