Update Vue mastery banner copy after promotion (#2814)

Author: pieer

themes/vue/layout/partials/vuemastery_banner.ejs

@@ -2,8 +2,8 @@
   <a href="https://www.vuemastery.com/free-weekend" target="_blank">
     <div class="vuemastery-banner--wrapper">
       <img class="vuemastery-banner--logo" src="/images/logo-vuemastery.svg" alt="vuemastery" />
-      <p><span>Watch all Vue Mastery courses</span>Free all weekend on April 23-25</p>
-      <button class="vuemastery-button">Register now</button>
+      <p><span>Save 35% off</span> a year of Vue courses</p>
+      <button class="vuemastery-button">Get access</button>
     </div>
     <div id="vm-close" class="vuemastery-banner--close"></div>
   </a>