文件上传组件有bug

[BrentHuang]

前后端分离，amis版本6.10.0，文件上传组件有bug，当选择一个文件时，字段名叫files，没问题；当选择多个文件时，字段名仍旧应该叫files，而不是files[]。bug如下图：

组件配置：“随表单提交”->“二进制”

 {
    "name": "files",
    "label": "打印文件",
    "type": "input-file",
    "id": "u:2f02280d2fae",
    "btnLabel": "文件上传",
    "uploadType": "asForm",
    "proxy": false,
    "autoUpload": true,
    "useChunk": false,
    "accept": "",
    "drag": false,
    "asBlob": true,
    "formType": "asBlob",
    "required": true,
    "multiple": true
}

可以用裸的html form表单做对比：

  <form action="http://localhost:8000/api/v1/slices/upload/" enctype="multipart/form-data" method="post">
    <label for="file-upload">选择文件：</label>
    <input type="file" id="file-upload" name="files" multiple>
    <br><br>
    <input type="submit" value="上传">
  </form>

上面的html代码，提交的数据截图如下：

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[BrentHuang]

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