添加 gitee 同步的 GitHub Action

[afc163]

以后不需要手动同步 Gitee 国内镜像仓库了，GitHub 提交后会自定同步。

• [x] antv.vision https://github.com/antvis/antvis.github.io/pull/69
• [x] g2.antv.vision https://github.com/antvis/G2/pull/2336
• [x] g2plot.antv.vision https://github.com/antvis/G2Plot/pull/944
• [x] g6.antv.vision https://github.com/antvis/G6/pull/1467
• [x] f2.antv.vision https://github.com/antvis/F2/pull/828
• [x] l7.antv.vision https://github.com/antvis/L7/pull/295
• [x] graphin.antv.vision https://github.com/antvis/Graphin/pull/83
• [x] g.antv.vision https://github.com/antvis/g/pull/487

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• https://github.com/marketplace/actions/gitee-pages-action
• https://juejin.im/post/5e58ef58e51d4526f16e4dab
• https://github.com/ant-design/ant-design/blob/master/.github/workflows/mirror.yml

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All done!