Bump the hooks-its-parent version to 2.8-SNAPSHOT

Change-Id: I30c7b72b0a7c51b8d5dfab7abeb57ba9e2e5c56e

pom.xml

diff --git a/pom.xml b/pom.xml
index c1f392c..002a5fa 100644
--- a/pom.xml
+++ b/pom.xml
@@ -20,7 +20,7 @@
   <parent>
     <groupId>com.googlesource.gerrit.plugins.its</groupId>
     <artifactId>hooks-its-parent</artifactId>
-    <version>2.6-SNAPSHOT</version>
+    <version>2.8-SNAPSHOT</version>
   </parent>
   <artifactId>hooks-jira</artifactId>
   <packaging>jar</packaging>