Remove unnecessary modifiers

Change-Id: I890c9b33ae8e8402520230860fa575a9ec757b2d
diff --git a/core/api/src/main/java/org/onosproject/net/flow/FlowRuleService.java b/core/api/src/main/java/org/onosproject/net/flow/FlowRuleService.java
index e297115..d4f959c 100644
--- a/core/api/src/main/java/org/onosproject/net/flow/FlowRuleService.java
+++ b/core/api/src/main/java/org/onosproject/net/flow/FlowRuleService.java
@@ -32,7 +32,7 @@
     /**
      * The topic used for obtaining globally unique ids.
      */
-    static String FLOW_OP_TOPIC = "flow-ops-ids";
+    String FLOW_OP_TOPIC = "flow-ops-ids";
 
     /**
      * Returns the number of flow rules in the system.