use stopwatch item for autolock tab

main/ui/src/main/java/org/cryptomator/ui/controls/FontAwesome5Icon.java

@@ -39,11 +39,11 @@ public enum FontAwesome5Icon {
 	REDO("\uF01E"), //
 	SEARCH("\uF002"), //
 	SPINNER("\uF110"), //
+	STOPWATCH("\uF2F2"), //
 	SYNC("\uF021"), //
 	TIMES("\uF00D"), //
 	TRASH("\uF1F8"), //
 	UNLINK("\uf127"), //
-	USER_LOCK("\uF502"), //
 	WRENCH("\uF0AD"), //
 	WINDOW_MINIMIZE("\uF2D1"), //
 	;

main/ui/src/main/resources/fxml/vault_options.fxml

@@ -38,7 +38,7 @@
 		</Tab>
 		<Tab fx:id="autoLockTab" id="AUTOLOCK" text="%vaultOptions.autoLock">
 			<graphic>
-				<FontAwesome5IconView glyph="USER_LOCK"/>
+				<FontAwesome5IconView glyph="STOPWATCH"/>
 			</graphic>
 			<content>
 				<fx:include source="/fxml/vault_options_autolock.fxml"/>