fix(textarea ): calculate the height of textarea after leaving the pa…

…ge (#4539)

* fix(textarea ): calculate the height of textarea after leaving the page

close #4472

* chore: fix

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Co-authored-by: wū yāng <uyarnchen@gmail.com>

src/textarea/textarea.tsx

@@ -138,6 +138,7 @@ export default defineComponent({
 
     const formItem = inject(FormItemInjectionKey, undefined);
     const emitBlur = (e: FocusEvent) => {
+      if (!e.target) return;
       adjustTextareaHeight();
       focused.value = false;
       props.onBlur?.(innerValue.value, { e });