Clean up wrappers created for tooltips when the parent option is given

FIX: Fix an issue that caused the tooltip system to leave empty nodes in the DOM when an
editor using the `parent` option to `tooltips` is destroyed.

Closes codemirror/dev#1253

src/tooltip.ts

@@ -225,6 +225,7 @@ const tooltipPlugin = ViewPlugin.fromClass(class {
       tooltipView.dom.remove()
       tooltipView.destroy?.()
     }
+    if (this.parent) this.container.remove()
     this.intersectionObserver?.disconnect()
     clearTimeout(this.measureTimeout)
   }