Enable a few eslint-config-xo rules (#34620)

* unicorn/prefer-dom-node-append
* unicorn/prefer-dom-node-remove

js/src/modal.js

@@ -217,7 +217,7 @@ class Modal extends BaseComponent {
 
     if (!this._element.parentNode || this._element.parentNode.nodeType !== Node.ELEMENT_NODE) {
       // Don't move modal's DOM position
-      document.body.appendChild(this._element)
+      document.body.append(this._element)
     }
 
     this._element.style.display = 'block'

js/src/tooltip.js

@@ -257,7 +257,7 @@ class Tooltip extends BaseComponent {
     Data.set(tip, this.constructor.DATA_KEY, this)
 
     if (!this._element.ownerDocument.documentElement.contains(this.tip)) {
-      container.appendChild(tip)
+      container.append(tip)
       EventHandler.trigger(this._element, this.constructor.Event.INSERTED)
     }
 
@@ -402,7 +402,7 @@ class Tooltip extends BaseComponent {
       if (this._config.html) {
         if (content.parentNode !== element) {
           element.innerHTML = ''
-          element.appendChild(content)
+          element.append(content)
         }
       } else {
         element.textContent = content.textContent

js/src/util/backdrop.js

@@ -102,7 +102,7 @@ class Backdrop {
       return
     }
 
-    this._config.rootElement.appendChild(this._getElement())
+    this._config.rootElement.append(this._getElement())
 
     EventHandler.on(this._getElement(), EVENT_MOUSEDOWN, () => {
       execute(this._config.clickCallback)