Description of problem:
keystone driver error while deploying RHOSP 10 

[stack@rhosp10 ~]$ ./overcloud-deploy-hostname.sh
Removing the current plan files
Uploading new plan files
Started Mistral Workflow. Execution ID: 0896e8ff-726f-4dd0-bd8d-d2f8bfb2d1a1
Plan updated
Deploying templates in the directory /tmp/tripleoclient-FsaTLH/tripleo-heat-templates
Started Mistral Workflow. Execution ID: f177ae07-14c0-482f-906a-2181a95d32fa
{u'execution': {u'id': u'f177ae07-14c0-482f-906a-2181a95d32fa',
                u'input': {u'container': u'overcloud',
                           u'queue_name': u'32bb6e03-bf76-4092-837f-1eddf5cd18c4',
                           u'timeout': 50},
                u'name': u'tripleo.deployment.v1.deploy_plan',
                u'params': {},
                u'spec': {u'input': [u'container',
                                     {u'timeout': 240},
                                     {u'queue_name': u'tripleo'}],
                          u'name': u'deploy_plan',
                          u'tasks': {u'add_validation_ssh_key': {u'name': u'add_validation_ssh_key',
                                                                 u'on-complete': u'deploy',
                                                                 u'type': u'direct',
                                                                 u'version': u'2.0',
                                                                 u'workflow': u'tripleo.validations.v1.add_validation_ssh_key_parameter container=<% $.container %>'},
                                     u'deploy': {u'action': u'tripleo.deployment.deploy timeout=<% $.timeout %> container=<% $.container %>',
                                                 u'name': u'deploy',
                                                 u'on-error': u'set_deployment_failed',
                                                 u'on-success': u'send_message',
                                                 u'type': u'direct',
                                                 u'version': u'2.0'},
                                     u'send_message': {u'action': u'zaqar.queue_post',
                                                       u'input': {u'messages': {u'body': {u'payload': {u'execution': u'<% execution() %>',
                                                                                                       u'message': u"<% $.get('message', '') %>",
                                                                                                       u'status': u"<% $.get('status', 'SUCCESS') %>"},
                                                                                          u'type': u'tripleo.deployment.v1.deploy_plan'}},
                                                                  u'queue_name': u'<% $.queue_name %>'},
                                                       u'name': u'send_message',
                                                       u'retry': u'count=5 delay=1',
                                                       u'type': u'direct',
                                                       u'version': u'2.0'},
                                     u'set_deployment_failed': {u'name': u'set_deployment_failed',
                                                                u'on-success': u'send_message',
                                                                u'publish': {u'message': u'<% task(deploy).result %>',
                                                                             u'status': u'FAILED'},
                                                                u'type': u'direct',
                                                                u'version': u'2.0'}},
                          u'version': u'2.0'}},
 u'message': u"Failed to run action [action_ex_id=eb49f388-088a-4d38-a1c4-d2c20aa169b6, action_cls='<class 'mistral.actions.action_factory.DeployStackAction'>', attributes='{}', params='{u'container': u'overcloud', u'timeout': 50}']\n ERROR: The Parameter (KeystoneNotificationDriver) was not defined in template.",

Not sure where we specify the keystone driver 

command executed for overcloud deployment as follows

#!/bin/bash

source /home/stack/stackrc

openstack overcloud deploy --templates -e /usr/share/openstack-tripleo-heat-templates/environments/network-isolation.yaml -e /home/stack/templates/network-environment.yaml  -e /home/stack/templates/bigswitch-config-ivs.yaml -e /home/stack/scheduler_hints_env.yaml  --compute-flavor baremetal --control-flavor baremetal --ceph-storage-flavor ceph-storage --compute-scale 1 --control-scale 1 --ceph-storage-scale 0 --neutron-network-type vlan  --neutron-disable-tunneling  --neutron-network-vlan-ranges 'datacentre:2000:2050' --ntp-server 10.8.29.9 --timeout 50

Version-Release number of selected component (if applicable):

RHOSP 10
How reproducible:
New deployment with RHOSP 10

Steps to Reproduce:
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Actual results:


Expected results:


Additional info: