TF-3410 Fix wrong font size label Folders in MailBoxLeftMenu

Signed-off-by: dab246 <tdvu@linagora.com>

lib/features/mailbox/presentation/mailbox_view.dart

@@ -280,11 +280,7 @@ class MailboxView extends BaseMailboxView {
               Expanded(
                 child: Text(
                   AppLocalizations.of(context).folders,
-                  style: const TextStyle(
-                    fontSize: 15,
-                    color: Colors.black,
-                    fontWeight: FontWeight.bold,
-                  ),
+                  style: ThemeUtils.textStyleM3BodyMedium2(color: Colors.black),
                 ),
               ),
               Row(children: [

lib/features/mailbox/presentation/mailbox_view_web.dart

@@ -185,11 +185,7 @@ class MailboxView extends BaseMailboxView {
                   ),
                   child: Text(
                     AppLocalizations.of(context).folders,
-                    style: const TextStyle(
-                      fontSize: 15,
-                      color: Colors.black,
-                      fontWeight: FontWeight.bold,
-                    ),
+                    style: ThemeUtils.textStyleM3BodyMedium2(color: Colors.black),
                   ),
                 ),
               ),