Remove deprecated tail_log function

This function has been deprecated for a long time, let's finally
remove it. It is only generating a warning anyway.

Depends-On: https://review.opendev.org/c/openstack/panko/+/763941
Change-Id: I02372642b94ef508aed28942fe49a09f3ad35728

devstack/plugin.sh

@@ -271,8 +271,6 @@ function start_aodh {
     if [[ "$AODH_DEPLOY" == "mod_wsgi" ]]; then
         enable_apache_site aodh
         restart_apache_server
-        tail_log aodh /var/log/$APACHE_NAME/aodh.log
-        tail_log aodh-api /var/log/$APACHE_NAME/aodh_access.log
     elif [ "$AODH_DEPLOY" == "uwsgi" ]; then
         run_process aodh-api "$AODH_BIN_DIR/uwsgi $AODH_UWSGI_FILE"
     else