fix: Picker should open when click on padding

fix ant-design/ant-design#21149

Author: zombieJ

src/Picker.tsx

@@ -289,6 +289,7 @@ function InnerPicker<DateType>(props: PickerProps<DateType>) {
 
     if (inputRef.current) {
       inputRef.current.focus();
+      triggerOpen(true);
     }
   };
 

tests/picker.spec.tsx

@@ -557,6 +557,7 @@ describe('Picker.Basic', () => {
 
     wrapper.find('.rc-picker').simulate('mouseUp');
     expect(inputElement.focus).toHaveBeenCalled();
+    expect(wrapper.isOpen()).toBeTruthy();
   });
 
   it('defaultOpenValue in timePicker', () => {