[Lens] Add scrolling to inline editing example (#174368)

## Summary

The multi-panel flyout didn't allow the user to scroll the editing
controls. All better now 🩹


b06996de-62ba-431a-9cb1-eb3c20be42ee

---------

Co-authored-by: Kibana Machine <42973632+kibanamachine@users.noreply.github.com>
Co-authored-by: Stratoula Kalafateli <efstratia.kalafateli@elastic.co>

x-pack/examples/lens_embeddable_inline_editing_example/public/flyout.tsx

@@ -86,6 +86,7 @@ function InlineEditingContent({
   const style = css`
     padding: 0;
     position: relative;
+    height: 100%;
    }
 `;
 
@@ -104,6 +105,7 @@ function InlineEditingContent({
         `}
         direction="column"
         ref={containerRef}
+        gutterSize="none"
       />
     </EuiPanel>
   );