Upgrade: Bump @hint versions

docs/docs/contributor-guide/getting-started/development-environment/index.html

@@ -8,8 +8,8 @@
 </ol>
 <h2 id=step-1-install-nodejs-and-yarn>Step 1: Install Node.js and yarn<a href="#step-1-install-nodejs-and-yarn" class="headerlink" title="Step 1: Install Node.js and yarn"></a></h2><p>Go to <a target="_blank" href="https://nodejs.org/en/download/current/" ><code>nodejs.org</code></a> to download and install the latest stable
 version of <code>Node.js</code> for your operating system.</p>
-<p>Go to <a target="_blank" href="https://classic.yarnpkg.com" ><code>https://classic.yarnpkg.com</code></a> to download and install the latest stable
-version of <code>classic yarn</code> for your operating system, <b>yarn v2 is not supported yet</b>. <code>webhint</code> uses <a target="_blank" href="https://yarnpkg.com/en/docs/workspaces" ><code>yarn</code>’s
+<p>Go to <a target="_blank" href="https://yarnpkg.com" ><code>yarnpkg.com</code></a> to download and install the latest stable
+version of <code>yarn</code> for your operating system. <code>webhint</code> uses <a target="_blank" href="https://yarnpkg.com/en/docs/workspaces" ><code>yarn</code>’s
 <code>workspaces</code></a> feature to maintain several packages in
 the same GitHub repo.</p>
 <h2 id=step-2-fork-and-checkout-your-own-webhint-repository>Step 2: Fork and checkout your own webhint repository<a href="#step-2-fork-and-checkout-your-own-webhint-repository" class="headerlink" title="Step 2: Fork and checkout your own webhint repository"></a></h2><p>Go to <a target="_blank" href="https://github.com/webhintio/hint" >https://github.com/webhintio/hint</a> and click the <code>Fork</code> button.

docs/docs/user-guide/concepts/formatters/index.html

@@ -28,7 +28,7 @@
 <ul>
 <li><p><a target="_blank" href="https://npmjs.com/package/@hint/formatter-json" ><code>@hint/formatter-json</code></a> does a <code>JSON.stringify()</code> of
 the results. Output is not user friendly:</p>
-<p><img src="/static/images/json-output-6f15a72cc8.png" alt="Example output for the json formatter"></p>
+<p><img src="/static/images/json-output-2bb9d2f869.png" alt="Example output for the json formatter"></p>
 </li>
 <li><p><a target="_blank" href="https://npmjs.com/package/@hint/formatter-stylish" ><code>@hint/formatter-stylish</code></a> prints the results in
 table format indicating the resource, line, and column:</p>

docs/docs/user-guide/hints/hint-no-protocol-relative-urls/index.html

@@ -25,9 +25,6 @@ <h2 id=why-is-this-important>Why is this important?<a href="#why-is-this-importa
 </li>
 </ul>
 </li>
-<li><p><a target="_blank" href="https://www.stevesouders.com/blog/2010/02/10/5a-missing-schema-double-download/" >Internet Explorer 7 and 8 will download a stylesheet twice if
-protocol-relative URLs are used for <code>&lt;link&gt;</code>s or <code>@import</code>s</a>.</p>
-</li>
 </ul>
 </li>
 <li><p>Security</p>