refactor(syncengine): const-qualify unnamed lambda parameter

Signed-off-by: Git'Fellow <12234510+solracsf@users.noreply.github.com>

Author: solracsf

src/libsync/syncengine.cpp

@@ -1225,7 +1225,7 @@ void SyncEngine::handleRemnantReadOnlyFolders()
         slotAddTouchedFile(_localPath + oneFolder->_file);
 
         if (oneFolder->_type == ItemType::ItemTypeDirectory) {
-            const auto deletionCallback = [this] (const QString &deleteItem, bool) {
+            const auto deletionCallback = [this] (const QString &deleteItem, const bool) {
                 slotAddTouchedFile(deleteItem);
             };