fix(v2): fix build caused when one tab item (#1938)

* fix(v2): fix build caused when one tab item

* Use React method

CHANGELOG-2.x.md

@@ -2,6 +2,7 @@
 
 ## Unreleased
 
+- **HOTFIX for 2.0.0-alpha.32** - Fix build compilation if exists only one code tab.
 - Add table of contents highlighting on scroll.
 
 ## 2.0.0-alpha.32

packages/docusaurus-theme-classic/src/theme/Tabs/index.js

@@ -5,7 +5,7 @@
  * LICENSE file in the root directory of this source tree.
  */
 
-import React, {useState} from 'react';
+import React, {useState, Children} from 'react';
 
 import classnames from 'classnames';
 
@@ -31,7 +31,11 @@ function Tabs(props) {
         ))}
       </ul>
       <div className="margin-vert--md">
-        {[...children].filter(child => child.props.value === selectedValue)[0]}
+        {
+          Children.toArray(children).filter(
+            child => child.props.value === selectedValue,
+          )[0]
+        }
       </div>
     </div>
   );