<tr> tag with class="header" displayed incorrectly

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Issue Checklist

[x] I am using the latest version of NexT.
[x] I have read the relevant documents of Hexo and NexT.
[x] I have reviewed the latest Roadmap on GitHub and searched for current issues, which does not help me.

Expected behavior

The following normal table will be rendered to this html code by hexo-renderer-pandoc.

| A| B |
| :-: | :-: |
|A1| B1|
|A2| B2|

...

|A3| B3|

<div class="table-container"><table>
<colgroup>
<col style="width: 16%">
<col style="width: 83%">
</colgroup>
<thead>
<tr class="header">
<th style="text-align: center;">A</th>
<th style="text-align: center;">B</th>
</tr>
</thead>
<tbody>
<tr class="odd">
<td style="text-align: center;"> A1</td>
<td style="text-align: center;"> B1</td>
</tr>
<tr class="even">
<td style="text-align: center;">A2</td>
<td style="text-align: center;"> B2</td>
</tr>

......

<tr class="odd">
<td style="text-align: center;">AN</td>
<td style="text-align: center;">BN</td>
</tr>
</tbody>
</table></div>

And should be displayed like this.

Actual behavior

Steps to reproduce the behavior

use npm to uninstall hexo-renderer-marked and install hexo-renderer-pandoc.
render a markdown table, then you will get the wrong display in your web page.
remove the class="header" in tag like the following html code, then it seems to be ok.

<div class="table-container"><table>
<colgroup>
<col style="width: 16%">
<col style="width: 83%">
</colgroup>
<thead>
<tr>
<th style="text-align: center;">A</th>
<th style="text-align: center;">B</th>
</tr>
</thead>
<tbody>
<tr class="odd">
<td style="text-align: center;"> A1</td>
<td style="text-align: center;"> B1</td>
</tr>
<tr class="even">
<td style="text-align: center;">A2</td>
<td style="text-align: center;"> B2</td>
</tr>

......

<tr class="odd">
<td style="text-align: center;">AN</td>
<td style="text-align: center;">BN</td>
</tr>
</tbody>
</table></div>

Environment Information

Node.js and NPM Information

v16.15.1
8.11.0

Package dependencies Information

hexo-site@0.0.0 C:\path\to\dir
├── @next-theme/plugins@8.15.1
├── hexo-asset-img@1.0.0
├── hexo-deployer-git@4.0.0
├── hexo-generator-archive@2.0.0
├── hexo-generator-category@2.0.0
├── hexo-generator-index@3.0.0
├── hexo-generator-tag@2.0.0
├── hexo-next-valine@2.1.0
├── hexo-renderer-ejs@2.0.0
├── hexo-renderer-pandoc@0.3.1
├── hexo-renderer-stylus@2.1.0
├── hexo-server@3.0.0
├── hexo-theme-landscape@0.0.3
├── hexo-theme-next@8.15.1
└── hexo@7.0.0-rc1

theme-next / hexo-theme-next

<tr> tag with class="header" displayed incorrectly #1725