erp5testnode: userhosts added to testnode buildout

- userhosts software is required by scalability test infrastructure to solve DNS of frontend urls

software/erp5testnode/software.cfg

@@ -9,6 +9,7 @@ extends =
   ../../component/shellinabox/buildout.cfg
   ../../component/pwgen/buildout.cfg
   ../../component/apache/buildout.cfg
+  ../../component/userhosts/buildout.cfg
   ../../stack/monitor/buildout.cfg
 
 parts =
@@ -20,6 +21,7 @@ parts =
   zip
   git
   apache
+  userhosts
 
 [slapos.cookbook-repository]
 revision = 9d1048222ee06e120ca8977a0a54332804caa8ca