Bump karaf from 3.0.5 to 3.0.8

Change-Id: Ic5bc130f5110f4ff9da6ec22d066a5dd3069288d
diff --git a/incubator/protobuf/pom.xml b/incubator/protobuf/pom.xml
index 94bc87a..32abcaf 100644
--- a/incubator/protobuf/pom.xml
+++ b/incubator/protobuf/pom.xml
@@ -63,7 +63,7 @@
                 <plugin>
                     <groupId>org.apache.karaf.tooling</groupId>
                     <artifactId>karaf-maven-plugin</artifactId>
-                    <version>3.0.5</version>
+                    <version>3.0.8</version>
                     <extensions>true</extensions>
                 </plugin>
             </plugins>