fix syntax in template (introduced in #478)

Signed-off-by: Dirk Thomas <dirk-thomas@users.noreply.github.com>

Author: dirk-thomas

job_templates/snippet/property_parameter-definition_common.xml.em

@@ -60,7 +60,7 @@ choices.remove(ubuntu_distro)
             <a class="string-array">
               <string>@ros_distro</string>
 @{
-choices = ['dashing', 'eloquent', 'foxy', 'rolling]
+choices = ['dashing', 'eloquent', 'foxy', 'rolling']
 choices.remove(ros_distro)
 }@
 @[for choice in choices]@