updated testing version

Author: Bilal Al

testing/pom.xml

@@ -5,7 +5,7 @@
     <parent>
         <groupId>io.split.client</groupId>
         <artifactId>java-client-parent</artifactId>
-        <version>4.12.0-rc3</version>
+        <version>4.12.0-rc4</version>
     </parent>
     <artifactId>java-client-testing</artifactId>
     <packaging>jar</packaging>