Remove unused parameter

mobile/lib/models/gallery/gallery_sections.dart

@@ -208,7 +208,6 @@ class GalleryGroups {
       title: groupType.getTitle(
         context,
         dailyFiles.first,
-        lastFile: dailyFiles.last,
       ),
       groupType: groupType,
     );

mobile/lib/ui/viewer/gallery/component/group/type.dart

@@ -46,7 +46,10 @@ extension GroupTypeExtension on GroupType {
     return true;
   }
 
-  String getTitle(BuildContext context, EnteFile file, {EnteFile? lastFile}) {
+  String getTitle(
+    BuildContext context,
+    EnteFile file,
+  ) {
     if (this == GroupType.day) {
       return _getDayTitle(context, file.creationTime!);
     } else if (this == GroupType.week) {