Table: column header can be costumed (#17291)

Author: ziyoung

packages/table/src/table-column.js

@@ -144,11 +144,10 @@ export default {
     },
 
     setColumnRenders(column) {
-      const specialTypes = Object.keys(cellForced);
       // renderHeader 属性不推荐使用。
       if (this.renderHeader) {
         console.warn('[Element Warn][TableColumn]Comparing to render-header, scoped-slot header is easier to use. We recommend users to use scoped-slot header.');
-      } else if (specialTypes.indexOf(column.type) === -1) {
+      } else if (column.type !== 'selection') {
         column.renderHeader = (h, scope) => {
           const renderHeader = this.$scopedSlots.header;
           return renderHeader ? renderHeader(scope) : column.label;