Remove the compute-admin section from tempest config

This commit removes the compute-admin section from the tempest config
file that devstack generates. These options have been removed from
the tempest config and aren't being used, so there is no reason to
keep them around.

Change-Id: I7500fe3b329b913c60fa505a5230db4a5d35d7f1

Author: mtreinish

lib/tempest

@@ -358,11 +358,6 @@ function configure_tempest {
     # TODO(mriedem): Remove the preserve_ports flag when Juno is end of life.
     iniset $TEMPEST_CONFIG compute-feature-enabled preserve_ports True
 
-    # Compute admin
-    iniset $TEMPEST_CONFIG "compute-admin" username $ADMIN_USERNAME
-    iniset $TEMPEST_CONFIG "compute-admin" password "$password"
-    iniset $TEMPEST_CONFIG "compute-admin" tenant_name $ADMIN_TENANT_NAME
-
     # Network
     iniset $TEMPEST_CONFIG network api_version 2.0
     iniset $TEMPEST_CONFIG network tenant_networks_reachable "$tenant_networks_reachable"