Remove backup on memories widget

mobile/lib/ui/home/memories/memory_cover_widget.dart

@@ -19,7 +19,7 @@ class MemoryCoverWidget extends StatefulWidget {
   static const aspectRatio = 0.68;
   static const horizontalPadding = 2.5;
   final double maxScaleOffsetX;
-  final String? title;
+  final String title;
 
   const MemoryCoverWidget({
     required this.memories,
@@ -28,7 +28,7 @@ class MemoryCoverWidget extends StatefulWidget {
     required this.maxHeight,
     required this.maxWidth,
     required this.maxScaleOffsetX,
-    this.title,
+    required this.title,
     super.key,
   });
 
@@ -47,11 +47,8 @@ class _MemoryCoverWidgetState extends State<MemoryCoverWidget> {
 
     final widthOfScreen = MediaQuery.sizeOf(context).width;
     final index = _getNextMemoryIndex();
-    final title = widget.title != null
-        ? widget.title! == "filler"
-            ? _getTitle(widget.memories[index])
-            : widget.title!
-        : _getTitle(widget.memories[index]);
+    final title = widget.title;
+
     final memory = widget.memories[index];
     final isSeen = memory.isSeen();
     final brightness =