fixed some bugs with the input event handler on the embeds example (#3516)

* fixed some bugs with the input event handler on the embeds example, got rid of the non functional 'is selected and is focused' conditions for showing the input.

* fix linting error

Co-authored-by: DamareYoh <34608378+DamareYoh@users.noreply.github.com>

site/examples/embeds.js

@@ -1,5 +1,5 @@
 import React, { useState, useMemo } from 'react'
-import { Editor, createEditor } from 'slate'
+import { Transforms, createEditor } from 'slate'
 import {
   Slate,
   Editable,
@@ -41,30 +41,10 @@ const Element = props => {
 
 const VideoElement = ({ attributes, children, element }) => {
   const editor = useEditor()
-  const selected = useSelected()
-  const focused = useFocused()
   const { url } = element
   return (
     <div {...attributes}>
-      <div
-        contentEditable={false}
-        style={{
-          position: 'relative',
-          boxShadow: selected && focused ? '0 0 0 3px #B4D5FF' : 'none',
-        }}
-      >
-        <div
-          style={{
-            display: selected && focused ? 'none' : 'block',
-            position: 'absolute',
-            top: '0',
-            left: '0',
-            height: '100%',
-            width: '100%',
-            cursor: 'cell',
-            zIndex: 1,
-          }}
-        />
+      <div contentEditable={false}>
         <div
           style={{
             padding: '75% 0 0 0',
@@ -83,7 +63,6 @@ const VideoElement = ({ attributes, children, element }) => {
             }}
           />
         </div>
-        {selected && focused ? (
         <input
           value={url}
           onClick={e => e.stopPropagation()}
@@ -91,12 +70,11 @@ const VideoElement = ({ attributes, children, element }) => {
             marginTop: '5px',
             boxSizing: 'border-box',
           }}
-            onChange={value => {
+          onChange={e => {
             const path = ReactEditor.findPath(editor, element)
-              Transforms.setNodes(editor, { url: value }, { at: path })
+            Transforms.setNodes(editor, { url: e.target.value }, { at: path })
           }}
         />
-        ) : null}
       </div>
       {children}
     </div>