docs: switch to suggesting jsDelivr as a CDN (#31898)

_config.yml

@@ -55,11 +55,11 @@ download:
 
 cdn:
   # See https://www.srihash.org for info on how to generate the hashes
-  css:              "https://stackpath.bootstrapcdn.com/bootstrap/4.5.3/css/bootstrap.min.css"
+  css:              "https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/css/bootstrap.min.css"
   css_hash:         "sha384-TX8t27EcRE3e/ihU7zmQxVncDAy5uIKz4rEkgIXeMed4M0jlfIDPvg6uqKI2xXr2"
-  js:               "https://stackpath.bootstrapcdn.com/bootstrap/4.5.3/js/bootstrap.min.js"
+  js:               "https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.min.js"
   js_hash:          "sha384-w1Q4orYjBQndcko6MimVbzY0tgp4pWB4lZ7lr30WKz0vr/aWKhXdBNmNb5D92v7s"
-  js_bundle:        "https://stackpath.bootstrapcdn.com/bootstrap/4.5.3/js/bootstrap.bundle.min.js"
+  js_bundle:        "https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.bundle.min.js"
   js_bundle_hash:   "sha384-ho+j7jyWK8fNQe+A12Hb8AhRq26LrZ/JpcUGGOn+Y7RsweNrtN/tE3MoK7ZeZDyx"
   jquery:           "https://code.jquery.com/jquery-3.5.1.slim.min.js"
   jquery_hash:      "sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj"

site/docs/4.5/getting-started/download.md

@@ -34,9 +34,9 @@ If you want to download and examine our [examples]({{ site.baseurl }}/docs/{{ si
 
 <a href="{{ site.download.dist_examples }}" class="btn btn-bd-primary" onclick="ga('send', 'event', 'Getting started', 'Download', 'Download Examples');">Download Examples</a>
 
-## BootstrapCDN
+## jsDelivr
 
-Skip the download with [BootstrapCDN](https://www.bootstrapcdn.com/) to deliver cached version of Bootstrap's compiled CSS and JS to your project.
+Skip the download with [jsDelivr](https://www.jsdelivr.com/) to deliver cached version of Bootstrap's compiled CSS and JS to your project.
 
 {% highlight html %}
 <link rel="stylesheet" href="{{ site.cdn.css }}" integrity="{{ site.cdn.css_hash }}" crossorigin="anonymous">

site/docs/4.5/getting-started/introduction.md

@@ -1,7 +1,7 @@
 ---
 layout: docs
 title: Introduction
-description: Get started with Bootstrap, the world's most popular framework for building responsive, mobile-first sites, with BootstrapCDN and a template starter page.
+description: Get started with Bootstrap, the world's most popular framework for building responsive, mobile-first sites, with jsDelivr and a template starter page.
 group: getting-started
 redirect_from:
   - "/docs/"
@@ -14,7 +14,7 @@ toc: true
 
 ## Quick start
 
-Looking to quickly add Bootstrap to your project? Use BootstrapCDN, provided for free by the folks at StackPath. Using a package manager or need to download the source files? [Head to the downloads page]({{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/download/).
+Looking to quickly add Bootstrap to your project? Use jsDelivr, a free open source CDN. Using a package manager or need to download the source files? [Head to the downloads page]({{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/download/).
 
 ### CSS
 

site/index.html

@@ -56,9 +56,9 @@ gem install bootstrap -v {{ site.current_ruby_version }}
         <div class="masthead-followup-icon d-inline-block mb-2 text-white bg-primary">
           {% include icons/cloud-fill.svg width="32" height="32" class="masthead-followup-svg" %}
         </div>
-        <h2>BootstrapCDN</h2>
+        <h2>jsDelivr</h2>
         <p class="lead font-weight-normal">
-          When you only need to include Bootstrap’s compiled CSS or JS, you can use <a href="https://www.bootstrapcdn.com/">BootstrapCDN</a>.
+          When you only need to include Bootstrap’s compiled CSS or JS, you can use <a href="https://www.jsdelivr.com/">jsDelivr</a>.
         </p>
         <p>
           See it in action with our simple <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/introduction/#starter-template">starter template</a>, or <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/examples/">browse the examples</a> to jumpstart your next project. You can also choose to include Popper.js and our JS <a href="{{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/introduction/#separate">separately</a>.