update core/src/components/datetime/datetime.tsx

Co-authored-by: Shane <shane@shanessite.net>

Author: os-davidlourenco

core/src/components/datetime/datetime.tsx

@@ -1034,7 +1034,7 @@ export class Datetime implements ComponentInterface {
             this.resolveForceDateScrolling();
           }
 
-          const activeEl = document.activeElement as HTMLElement | null;
+          const activeEl = this.el.shadowRoot!.activeElement as HTMLElement | null;
           if (activeEl) {
             activeEl.blur();
             calendarBodyRef.focus();