Minor fix in head

Author: marshka

_includes/head.html

@@ -14,11 +14,11 @@
     <meta name="twitter:card" content="summary_large_image">
 
     {% if page.title %}
-    <meta property="og:title" content="{{site.title}}">
-    <meta name="twitter:title" content="{{site.title}}">
-    {% else %}
     <meta property="og:title" content="{{site.title}} / {{page.title}}">
     <meta name="twitter:title" content="{{site.title}} / {{page.title}}">
+    {% else %}
+    <meta property="og:title" content="{{site.title}}">
+    <meta name="twitter:title" content="{{site.title}}">
     {% endif %}
 
     {% if page.description %}

_tutorials/graph-based-processing/ecml-2023.html

@@ -4,7 +4,7 @@
 lead: Forecasting, Reconstruction and Analysis
 description: The GMLG tutorial on graph deep learning for time-series processing.
 venue: ECML PKDD 2023
-image: tutorials/graph-based-processing/img/thumb.jpg
+image: tutorials/graph-based-processing/img/thumb.jpg?v=2
 ---
 <!-- Outline section-->
 <section>