Remove deprecated config options usage

Tempest has deprecated the allow_tenant_isolation config option
of auth and compute groups since 3 years in I78a4884e980ef7d0103639cb3792a54c69fb7761.

Now Tempest patch - https://review.openstack.org/#/c/582698/ is removing
this deprecated options.

This commit remove the usage of deprecated or already removed
tempest config options from tripleo.sh.

Change-Id: I122a52a04ae7186163a0f027edce3bce8f0d8116
Needed-By: https://review.openstack.org/#/c/582698/

scripts/tripleo.sh

@@ -1184,16 +1184,15 @@ function tempest_run {
         --create \
         --deployer-input ~/tempest-deployer-input.conf \
         identity.uri $OS_AUTH_URL \
-        compute.allow_tenant_isolation true \
+        auth.use_dynamic_credentials true \
         identity.admin_password $OS_PASSWORD \
         compute.build_timeout 500 \
-        compute.image_ssh_user cirros \
+        validation.image_ssh_user cirros \
         orchestration.stack_owner_role _member_ \
-        compute.ssh_user cirros \
         network.build_timeout 500 \
         volume.build_timeout 500 \
         DEFAULT.log_file "/var/log/tempest/tempest.log" \
-        scenario.ssh_user cirros $TEMPEST_ADD_CONFIG
+        $TEMPEST_ADD_CONFIG
     sudo cp $HOME/tempest/etc/tempest.conf /etc/tempest/tempest.conf
     [[ ! -e $HOME/tempest/.testrepository ]] && $HOME/tempest/tools/with_venv.sh testr init
     $HOME/tempest/tools/with_venv.sh testr run \