🎨 Optimize the null check in list

lib/widgets/post/post_item.dart

@@ -478,10 +478,7 @@ class PostItem extends HookConsumerWidget {
 
     final translationSection = Column(
       crossAxisAlignment: CrossAxisAlignment.stretch,
-      children: [
-        if (translatedWidget != null) translatedWidget,
-        if (translatableWidget != null) translatableWidget,
-      ],
+      children: [?translatedWidget, ?translatableWidget],
     );
 
     return Column(

lib/widgets/post/post_shared.dart

@@ -854,7 +854,7 @@ class PostHeader extends HookConsumerWidget {
                 ],
               ),
             ),
-            if (trailing != null) trailing!,
+            ?trailing,
           ],
         ),
       ],
@@ -1142,7 +1142,7 @@ class PostBody extends ConsumerWidget {
                   attachments: item.attachments,
                   noMentionChip: item.fediverseUri != null,
                 ),
-                if (translationSection != null) translationSection!,
+                ?translationSection,
               ],
             ),
           ),