Set version to 2.6-rc2 to match the Gerrit release

Change-Id: If8cc559fd8b38d041c8c1f9a9c72d31dd547879c
diff --git a/pom.xml b/pom.xml
index f170995..aee0e29 100644
--- a/pom.xml
+++ b/pom.xml
@@ -22,7 +22,7 @@
   <artifactId>commit-message-length-validator</artifactId>
   <groupId>com.googlesource.gerrit.plugins.validators</groupId>
   <packaging>jar</packaging>
-  <version>2.8-SNAPSHOT</version>
+  <version>2.6-rc2</version>
 
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>