Unable to add multiple properties to local registry

[GDLMadushanka]

Description: Adding multiple properties to a registry resource failed when done via property mediators. Its working correctly in management console.

Suggested Labels: Bug

Affected Product Version: EI 6.6.0

Steps to reproduce: Deploy the following API and invoke Only the last property is getting added. ( it replaces the previous properties )

<api xmlns="http://ws.apache.org/ns/synapse" name="AddRegProperty" context="/test">
    <resource methods="GET">
        <inSequence>
            <property name="maxxingKey" value="15"/>
            <property name="lifeTime" value="6"/>
            <property name="local:customers/maxxing/oAuthKey.txt@maxxingKey" expression="$ctx:maxxingKey" scope="registry"/>
            <property name="local:customers/maxxing/oAuthKey.txt@lifeTime" expression="$ctx:lifeTime" scope="registry"/>
            <respond/>
        </inSequence>
        <outSequence/>
        <faultSequence/>
    </resource>
</api>