在块级元素上设置class或style属，插入编辑器中无效

Describe the bug or issue here…

##### Steps to Reproduce

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##### Details

* Trix version:
* Browser name and version:
* Operating system:

Start by creating a minimal reproduction in the Trix editor using a block-level element with class or style attributes. The issue is complete when those attributes remain effective after the element is inserted into the editor; the payload does not identify a source file or test to run.

Written by the indexing model from the issue text.