Fix the broken links when select versions

_includes/version-select.html

@@ -13,7 +13,7 @@
             {% for ver in site.pegasus_versions %}
 
             <!--URL of our latest version always starts without version prefixed.-->
-            {% assign version_prefix = '/' | append: page.version %}
+            {% assign version_prefix = page.version | append: '/' %}
             {% assign no_version_link = page.permalink | remove_first: version_prefix %}
             {% if ver == site.latest_pegasus_version %}
             {% assign version_url = no_version_link %}