[DataViews] Fix form validation UX when the same data view name already exists (#146126)

Closes https://github.com/elastic/kibana/issues/138958

## Summary

This PR fixes form UX when the same data view name already exists.

![Nov-23-2022
11-35-34](https://user-images.githubusercontent.com/1415710/203527157-6659b74b-774f-4619-a6c7-553f0f87e6e6.gif)

src/plugins/data_view_editor/public/components/data_view_editor_flyout_content.tsx

@@ -339,7 +339,12 @@ const IndexPatternEditorFlyoutContentComponent = ({
             })}
           </EuiLink>
         )}
-        <Form form={form} className="indexPatternEditor__form">
+        <Form
+          form={form}
+          className="indexPatternEditor__form"
+          error={form.getErrors()}
+          isInvalid={form.isSubmitted && !form.isValid}
+        >
           <UseField path="isAdHoc" />
           {indexPatternTypeSelect}
           <EuiSpacer size="l" />