Revert "set pom version to 0.7"

This reverts commit e0a78a338566ed8b9cbe33352a03ff66a8477a61.
diff --git a/releng/org.eclipse.gendoc.update-site/pom.xml b/releng/org.eclipse.gendoc.update-site/pom.xml
index 085cfc9..d2b061e 100644
--- a/releng/org.eclipse.gendoc.update-site/pom.xml
+++ b/releng/org.eclipse.gendoc.update-site/pom.xml
@@ -4,7 +4,7 @@
   <parent>
   <groupId>org.eclipse.gendoc</groupId>
   <artifactId>parent</artifactId>
-  <version>0.7.0-SNAPSHOT</version>
+  <version>0.6.0-SNAPSHOT</version>
   <relativePath>../../pom.xml</relativePath>
   </parent>