fix(markdown): pass container option to gitHubAlertsPlugin

[niansi-z]

Description

GitHub-flavored Alerts
Cannot set global custom titles by configuring markdown.container.

// config.ts
export default defineConfig({
  // ...
  markdown: {
    container: {
      infoLabel: '相关信息',
      noteLabel: '注',
      tipLabel: '提示',
      warningLabel: '注意',
      dangerLabel: '危险',
      detailsLabel: '详情',
      importantLabel: '重要',
      cautionLabel: '警告'
    }
  }
  // ...
})

[niansi-z]

I didn't understand why GitHub-flavored Alerts say "They will be rendered the same as the custom containers," but it's not possible to modify the global custom titles through the container configuration.