fix(timepicker): correctly set initial time manually (#2945)

Author: valorkin

src/timepicker/timepicker.component.ts

@@ -203,7 +203,8 @@ export class TimepickerComponent
   }
 
   _updateTime() {
-    if (!isInputValid(this.hours, this.minutes, this.seconds, this.isPM())) {
+    const _seconds = this.showSeconds ? this.seconds : void 0;
+    if (!isInputValid(this.hours, this.minutes, _seconds, this.isPM())) {
       this.onChange(null);
 
       return;