Update Babel documentation (7.21.1)

See #1926

lib/docs/filters/babel/clean_html.rb

@@ -3,6 +3,8 @@ module Docs
     class CleanHtmlFilter < Filter
       def call
 
+        @doc = at_css('.theme-doc-markdown')
+
         css('.fixedHeaderContainer').remove
 
         css('.toc').remove
@@ -15,14 +17,17 @@ module Docs
 
         css('.docs-prevnext').remove
 
-        css('pre > code.hljs').each do |node|
-          node.parent['data-language'] = node['class'][/language-(\w+)/, 1]
-        end
-
         css('pre').each do |node|
-          node.content = node.content
+          node.content = node.css('.token-line').map(&:content).join("\n")
+          node['data-language'] = node['class'][/language-(\w+)/, 1]
         end
 
+        css('.codeBlockTitle_x_ju').remove
+
+        css('*').remove_attr('class')
+
+        css('*').remove_attr('style')
+
         doc
 
       end

lib/docs/scrapers/babel.rb

@@ -1,7 +1,7 @@
 module Docs
   class Babel < UrlScraper
     self.type = 'simple'
-    self.base_url = 'https://babeljs.io/docs/en/'
+    self.base_url = 'https://babeljs.io/docs/'
     self.links = {
       home: 'https://babeljs.io/',
       code: 'https://github.com/babel/babel'
@@ -30,7 +30,7 @@ module Docs
     HTML
 
     version '7' do
-      self.release = '7.16.4'
+      self.release = '7.21.1'
     end
 
     version '6' do