provide prefixCls on icon

[ikeq]

期望 icon 组件也能够提供自定义 class 前缀设置，目前是硬编码的

ant-design-vue/components/icon/index.js

Line 49 in 48bf9ff

[`anticon`]: true,

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[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.