v2.7.5

Clocker

• [fix] fix this.clocker maybe undefined on hook:beforeDestroy #2258

Panel

• [fix] remove duplicate top border
• [feature] add slot:header slot:body #2270

XButton

• [fix] fix plain and disabled class error

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Clocker

• [fix] 修复 beforeDestroy 调用时 this.clocker 不存在 #2258

Panel

• [fix] 移除重复顶部边框样式
• [feature] 添加 slot:header slot:body #2270

XButton

• [fix] 修复plain样式并禁用时class不对的问题