i[dates global header to make site title a yaml thing

components/vf-global-header/vf-global-header.config.yml

@@ -3,3 +3,5 @@ label: Global Header
 preview: '@preview--containers'
 context:
   component-type: block
+
+  text: Visual Framework for Life Science websites

components/vf-global-header/vf-global-header.njk

@@ -4,7 +4,7 @@
 
     {% render '@vf-logo--responsive' %}
 
-    <p class="vf-global-header__site-name">Visual Framework for Life Science websites</p>
+    <p class="vf-global-header__site-name">{{ text }}</p>
 
     {% render '@vf-navigation--global' %}