better toString output for the max instance count attribute

Author: mkiener

modules/flowable-cmmn-model/src/main/java/org/flowable/cmmn/model/RepetitionRule.java

@@ -79,7 +79,7 @@ public void setMaxInstanceCount(Integer maxInstanceCount) {
     @Override
     public String toString() {
         return "RepetitionRule{" +
-                " maxInstanceCount='" + maxInstanceCount + "'" +
+                " maxInstanceCount='" + (hasLimitedInstanceCount() ? maxInstanceCount : "unlimited") + "'" +
                 " repetitionCounterVariableName='" + repetitionCounterVariableName + "'" +
                 " collectionVariableName='" + collectionVariableName + "'" +
                 " elementVariableName='" + elementVariableName + "'" +