provide LOCK token when uploading a single file via PUT

for simple webDAV upload via PUT verb, provide the needed lock token

Signed-off-by: Matthieu Gallien <matthieu.gallien@nextcloud.com>

src/libsync/propagateuploadv1.cpp

@@ -102,6 +102,10 @@ void PropagateUploadFileV1::startNextChunk()
 
     QString path = _fileToUpload._file;
 
+    if (_item->_locked == SyncFileItem::LockStatus::LockedItem) {
+        headers[QByteArrayLiteral("If")] = (QLatin1String("<") + propagator()->account()->davUrl().toString() + _fileToUpload._file + "> (<opaquelocktoken:" + _item->_lockToken.toUtf8() + ">)").toUtf8();
+    }
+
     qint64 chunkStart = 0;
     qint64 currentChunkSize = fileSize;
     bool isFinalChunk = false;