feat(Popover): add icon-prefix prop (#8703)

* fix: popover 增加 icon-prefix 属性

* fix: popover icon-prefix属性跑单测

Co-authored-by: 冷开俊 <lengkj@travelsky.com.cn>

src/popover/test/__snapshots__/index.spec.tsx.snap

@@ -10,6 +10,11 @@ exports[`should allow to custom the className of action 1`] = `
 </div>
 `;
 
+exports[`should change icon class prefix when using icon-prefix prop 1`] = `
+<span class="van-popover__wrapper">
+</span>
+`;
+
 exports[`should locate to reference element when showed 1`] = `
 <transition-stub>
 </transition-stub>

src/popover/test/index.spec.tsx

@@ -187,3 +187,15 @@ test('should not close Popover when outside is clicked and close-on-click-outsid
   trigger(document.body, 'touchstart');
   expect(wrapper.emitted('update:show')).toBeFalsy();
 });
+
+test('should change icon class prefix when using icon-prefix prop', () => {
+  const wrapper = mount(Popover, {
+    props: {
+      show: true,
+      icon: 'success',
+      iconPrefix: 'my-icon',
+    },
+  });
+
+  expect(wrapper.html()).toMatchSnapshot();
+});