fix(datetime): next and previous buttons have correct labels (#25845)

resolves #25844

Author: liamdebeasi

core/src/components/datetime/datetime.tsx

@@ -1839,11 +1839,11 @@ export class Datetime implements ComponentInterface {
 
           <div class="calendar-next-prev">
             <ion-buttons>
-              <ion-button disabled={prevMonthDisabled} onClick={() => this.prevMonth()}>
-                <ion-icon slot="icon-only" icon={chevronBack} lazy={false} flipRtl></ion-icon>
+              <ion-button aria-label="previous month" disabled={prevMonthDisabled} onClick={() => this.prevMonth()}>
+                <ion-icon aria-hidden="true" slot="icon-only" icon={chevronBack} lazy={false} flipRtl></ion-icon>
               </ion-button>
-              <ion-button disabled={nextMonthDisabled} onClick={() => this.nextMonth()}>
-                <ion-icon slot="icon-only" icon={chevronForward} lazy={false} flipRtl></ion-icon>
+              <ion-button aria-label="next month" disabled={nextMonthDisabled} onClick={() => this.nextMonth()}>
+                <ion-icon aria-hidden="true" slot="icon-only" icon={chevronForward} lazy={false} flipRtl></ion-icon>
               </ion-button>
             </ion-buttons>
           </div>