Flow Remove and Add arrive simultaneously from ONOS to ofagent on subscriber provision

When subscriber is provisioned (for ATT workflow), the EAP is deleted  and then flows are provisioned with subscriber tags. ONOS needs to wait for EAP Flow Delete Ack before provisioning the subscriber flows. But in job here https://jenkins.opencord.org/job/verify_physical_voltha_patchset_manual/574/ , it is seen that flow-delete and flow-add landed at ofagent at the same timestamp and the stack processed flow-add   first and then flow-delete. This will create an issue in both OLT and ONU adapter and consequently a wrong configuration is installed on the device. 

The test steps are 

1. Disable ONU.     19:52:54.025
2. Unprovision sub 19:53:05.192
3. Enable ONU.      19:53:09.500
4. Provision Sub.     19:53:23.166

The issue is seen at step4. 

In Ofagent logs, at time stamp 2020-08-11T19:53:23.179, flow add and delete land simultaneously.

Note: If the afore mentioned job is unavailable, please download the attached logs.