Fix #5573 🐛 Fix the Selected Year Picker style when no date is selected

src/test/year_picker_test.test.tsx

@@ -148,6 +148,20 @@ describe("YearPicker", () => {
     expect(yearElements.length).toBe(0);
   });
 
+  it("should not has selected class where there is no selectedDates", () => {
+    const { container } = render(
+      <Year
+        date={new Date()}
+        onYearMouseEnter={() => {}}
+        onYearMouseLeave={() => {}}
+      />,
+    );
+    const yearElements = Array.from(
+      container.querySelectorAll(".react-datepicker__year-text--selected"),
+    );
+    expect(yearElements.length).toBe(0);
+  });
+
   it("should have current year class when element of array equal of current year", () => {
     const date = new Date();
     const { container } = render(

src/year.tsx

@@ -248,7 +248,7 @@ export default class Year extends Component<YearProps> {
     if (selectsMultiple) {
       return selectedDates?.some((date) => year === getYear(date));
     }
-    return !selected || year === getYear(selected);
+    return !!selected && year === getYear(selected);
   };
 
   onYearClick = (