fix(upload-client/multipart): set custom chunk size when starting multipart upload

If a multipart upload is started with a custom part size, the part size must be set in the request to `/multipart/start/` via `part_size`. Otherwise, the default 5 MB part size is used, which causes the subsequent request to `/multipart/complete/` to fail with the following error:

```
{
    "error":
    {
        "status_code": 400,
        "content": "Can not complete upload. Wrong parts size?",
        "error_code": "MultipartFileCompletionFailedError"
    }
}
```

Author: optlsnd

packages/upload-client/src/uploadFile/uploadMultipart.ts

@@ -143,7 +143,8 @@ export const uploadMultipart = async (
     userAgent,
     retryThrottledRequestMaxTimes,
     retryNetworkErrorMaxTimes,
-    metadata
+    metadata,
+    multipartChunkSize
   })
     .then(async ({ uuid, parts }) => {
       const getChunk = await prepareChunks(file, size, multipartChunkSize)