[FIX] website: keep 'save/discard' btns consistent using themes

task-2335267
part-of: #57942

addons/website/static/src/scss/website.wysiwyg.scss

@@ -36,8 +36,9 @@
     .btn {
         border: none;
         border-radius: 0;
-        font-size: $o-we-sidebar-font-size;
-        font-weight: 700;
+        font-size: $o-we-font-size;
+        font-family: $o-we-font-family;
+        font-weight: 400;
         line-height: 1;
 
         &.btn-primary {