fix: content가 빈 문자열이어도 작성 가능하도록 수정

Author: opficdev

DevLog/Presentation/ViewModel/TodoEditorViewModel.swift

@@ -45,8 +45,7 @@ final class TodoEditorViewModel: Store {
         var hasDueDate: Bool { dueDate != nil }
         var tabViewTag: Tag = .editor
         var isValidToSave: Bool {
-            !title.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty &&
-            !content.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty
+            !title.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty
         }
     }