chore(deps): bump mathjax from 3.2.2 to 4.x

_data/origin/cors.yml

@@ -51,4 +51,4 @@ clipboard:
   js: https://cdn.jsdelivr.net/npm/clipboard@2.0.11/dist/clipboard.min.js
 
 mathjax:
-  js: https://cdn.jsdelivr.net/npm/mathjax@3.2.2/es5/tex-chtml.js
+  js: https://cdn.jsdelivr.net/npm/mathjax@4/tex-mml-chtml.js

_includes/js-selector.html

@@ -67,7 +67,6 @@
 {% if page.math %}
   <!-- MathJax -->
   <script src="{{ '/assets/js/data/mathjax.js' | relative_url }}"></script>
-  <script async src="https://cdnjs.cloudflare.com/polyfill/v3/polyfill.min.js?features=es6"></script>
   <script id="MathJax-script" async src="{{ site.data.origin[type].mathjax.js | relative_url }}"></script>
 {% endif %}
 

_sass/base/_base.scss

@@ -391,8 +391,9 @@ main {
 
 /* MathJax */
 mjx-container {
-  overflow-y: hidden;
-  min-width: auto !important;
+  a {
+    display: inline-block;
+  }
 }
 
 @media (hover: hover) {