feat: optimize head tags (#40630)

Co-authored-by: moT01 <20648924+moT01@users.noreply.github.com>

client/utils/tags.js

@@ -0,0 +1,85 @@
+import React from 'react';
+import { withPrefix } from 'gatsby';
+import i18next from 'i18next';
+
+export const getheadTagComponents = () => {
+  const socialImage =
+    'https://cdn.freecodecamp.org/platform/universal/fcc_meta_1920X1080-indigo.png';
+  const pathToBootstrap = withPrefix('/css/bootstrap.min.css');
+  return [
+    <link
+      as='style'
+      href={pathToBootstrap}
+      key='boostrap-min-preload'
+      rel='preload'
+    />,
+    <link href={pathToBootstrap} key='boostrap-min' rel='stylesheet' />,
+    <meta content='freeCodeCamp.org' key='og:title' name='og:title' />,
+    <meta
+      content={i18next.t('meta.social-description')}
+      key='og:description'
+      name='og:description'
+    />,
+    <meta content={socialImage} key='og:image' property='og:image' />,
+    <meta
+      content='summary_large_image'
+      key='twitter:card'
+      name='twitter:card'
+    />,
+    <meta
+      content={socialImage}
+      key='twitter:image:src'
+      name='twitter:image:src'
+    />,
+    <meta
+      content='freeCodeCamp.org'
+      key='twitter:title'
+      name='twitter:title'
+    />,
+    <meta
+      content={i18next.t('meta.social-description')}
+      key='twitter:description'
+      name='twitter:description'
+    />,
+    <meta
+      content='$ilp.uphold.com/LJmbPn7WD4JB'
+      key='monetization'
+      name='monetization'
+    />
+  ];
+};
+
+export const getPostBodyComponents = pathname => {
+  let scripts = [];
+  const challengesPathRE = new RegExp('/learn/[^/]+/[^/]+/[^/]+/?$');
+  const donatePathRE = new RegExp('/donate/?$');
+  const mathJaxScriptElement = (
+    <script
+      async={false}
+      id='mathjax'
+      key='mathjax'
+      src='https://cdnjs.cloudflare.com/ajax/libs/mathjax/2.7.4/MathJax.js?config=TeX-AMS_HTML'
+      type='text/javascript'
+    />
+  );
+  const stripeScriptElement = (
+    <script
+      async={true}
+      id='stripe-js'
+      key='stripe-js'
+      src='https://js.stripe.com/v3/'
+      type='text/javascript'
+    />
+  );
+
+  if (
+    pathname.includes('/learn/coding-interview-prep/rosetta-code') ||
+    pathname.includes('/learn/coding-interview-prep/project-euler')
+  ) {
+    scripts.push(mathJaxScriptElement);
+  }
+  if (challengesPathRE.test(pathname) || donatePathRE.test(pathname)) {
+    scripts.push(stripeScriptElement);
+  }
+  return scripts.filter(Boolean);
+};