Picker fix for validateForm (#2661)

Author: M-i-k-e-l

src/components/picker/helpers/useImperativePickerHandle.ts

@@ -6,7 +6,7 @@ const useImperativePickerHandle = (ref: React.Ref<any>,
   expandableRef: React.MutableRefObject<ExpandableOverlayMethods | null>) => {
   const pickerRef = useRef<TextFieldMethods>();
   useImperativeHandle(ref, () => {
-    const {isFocused, focus, blur, clear, validate} = pickerRef.current ?? {};
+    const {isFocused, focus, blur, clear, validate, isValid} = pickerRef.current ?? {};
     // @ts-expect-error useRef return type is possible null therefor it throw TS error
     const {openExpandable, closeExpandable, toggleExpandable} = expandableRef.current;
 
@@ -16,6 +16,7 @@ const useImperativePickerHandle = (ref: React.Ref<any>,
       blur,
       clear,
       validate,
+      isValid,
       openExpandable,
       closeExpandable,
       toggleExpandable