Fix combobox popover position

Signed-off-by: stephann <3025661+stephannv@users.noreply.github.com>

lib/ruby_ui/combobox/combobox_controller.js

@@ -54,7 +54,7 @@ export default class extends Controller {
   openPopover(event) {
     event.preventDefault()
 
-    this.popoverTarget.style.positionAnchor
+    this.updatePopoverPosition()
     this.triggerTarget.ariaExpanded = "true"
     this.selectedItemIndex = null
     this.itemTargets.forEach(item => item.ariaCurrent = "false")