Update Bootstrap documentation (5.3)

Fixes #1939.

assets/stylesheets/pages/_bootstrap.scss

@@ -8,6 +8,8 @@
     float: right;
   }
 
+  .h5 { font-size: 1.25rem; }
+
   .bs-callout { @extend %note; }
   .bs-callout-info { @extend %note-blue; }
   .bs-callout-danger { @extend %note-red; }
@@ -36,6 +38,7 @@
   }
 
   .col { margin-bottom: 1.5em; }
+  .d-block { display: block; }
 
   @media (min-width: 800px) {
     .row {
@@ -50,5 +53,6 @@
       -moz-box-sizing: border-box;
            box-sizing: border-box;
     }
+    .col-md-6 { width: 50%; }
   }
 }

lib/docs/scrapers/bootstrap.rb

@@ -10,8 +10,7 @@ module Docs
 
     # https://github.com/twbs/bootstrap/blob/master/LICENSE
     options[:attribution] = <<-HTML
-      &copy; 2011&ndash;2022 Twitter, Inc.<br>
+      &copy; 2011&ndash;2023 The Bootstrap Authors<br>
-      &copy; 2011&ndash;2022 The Bootstrap Authors<br>
       Code licensed under the MIT License.<br>
       Documentation licensed under the Creative Commons Attribution License v3.0.
     HTML
@@ -23,9 +22,8 @@ module Docs
 
       html_filters.push 'bootstrap/entries_v5', 'bootstrap/clean_html_v5'
 
-      options[:only_patterns] = [
+      options[:skip_patterns] = [
-        /\Agetting-started\//, /\Alayout\//, /\Acontent\//,
+        /\Aabout\//
-        /\Acomponents\//, /\Autilities\/.+/, /\Ahelpers\//
       ]
 
       options[:replace_paths] = {