chore: remove some unnecessary todos (#1785)

* chore: remove some unnecessary todos

* fix: the vertical padding for editor should be 28

Author: LucasXu0

frontend/app_flowy/lib/plugins/document/editor_styles.dart

@@ -9,7 +9,7 @@ EditorStyle customEditorTheme(BuildContext context) {
       ? EditorStyle.dark
       : EditorStyle.light;
   editorStyle = editorStyle.copyWith(
-    padding: const EdgeInsets.symmetric(horizontal: 100),
+    padding: const EdgeInsets.symmetric(horizontal: 100, vertical: 28),
     textStyle: editorStyle.textStyle?.copyWith(
       fontFamily: 'poppins',
       fontSize: documentStyle.fontSize,

frontend/app_flowy/lib/workspace/presentation/settings/widgets/settings_file_exporter_widget.dart

@@ -56,7 +56,6 @@ class _FileExporterWidgetState extends State<FileExporterWidget> {
         FlowyTextButton(
           LocaleKeys.button_OK.tr(),
           onPressed: () async {
-            // TODO: Export Data
             await getIt<FilePickerService>()
                 .getDirectoryPath()
                 .then((exportPath) {

frontend/app_flowy/lib/workspace/presentation/widgets/emoji_picker/emoji_picker.dart

@@ -2,4 +2,3 @@ export 'src/config.dart';
 export 'src/models/emoji_model.dart';
 export 'src/emoji_picker.dart';
 export 'src/emoji_picker_builder.dart';
-export 'src/emoji_button.dart';

frontend/app_flowy/lib/workspace/presentation/widgets/emoji_picker/src/emoji_button.dart

@@ -7,7 +7,6 @@ import 'package:flutter_math_fork/flutter_math.dart';
 const String kMathEquationType = 'math_equation';
 const String kMathEquationAttr = 'math_equation';
 
-// TODO: l10n
 SelectionMenuItem mathEquationMenuItem = SelectionMenuItem(
   name: () => 'Math Equation',
   icon: (editorState, onSelected) => Icon(