Bump apex master to 2.4.0

Issue-ID: POLICY-2514
Change-Id: I764cfe41ed8cf8ffebd4ff076d0b76b79d61e142
Signed-off-by: RossC <ross.carter@est.tech>
diff --git a/model/pom.xml b/model/pom.xml
index 4ca52a5..6312584 100644
--- a/model/pom.xml
+++ b/model/pom.xml
@@ -22,7 +22,7 @@
     <parent>
         <groupId>org.onap.policy.apex-pdp</groupId>
         <artifactId>apex-pdp</artifactId>
-        <version>2.3.3-SNAPSHOT</version>
+        <version>2.4.0-SNAPSHOT</version>
     </parent>
 
     <groupId>org.onap.policy.apex-pdp.model</groupId>