Change double quotes to single quotes

templates/_includes/_defaults.html

@@ -42,7 +42,7 @@
 
 {# Label to show before Share Post links #}
 {% if not SHARE_POST_INTRO %}
-{% set SHARE_POST_INTRO = "Share on:" %}
+{% set SHARE_POST_INTRO = 'Share on:' %}
 {% else %}
 {% set SHARE_POST_INTRO = SHARE_POST_INTRO %}
 {% endif %}