Bump the protobuf shaded version to 2.6.1

Signed-off-by: xiaolong.ran <[email protected]>

Author: wolfstudy

protobuf-shaded/pom.xml

@@ -26,7 +26,7 @@
   <parent>
     <groupId>org.apache.pulsar</groupId>
     <artifactId>pulsar</artifactId>
-    <version>2.7.0-SNAPSHOT</version>
+    <version>2.6.1</version>
     <relativePath>..</relativePath>
   </parent>