Replace "ara generate" by "ara generate html"

The newest version of ARA, 0.11, deprecated "ara generate" in favor
of "ara generate html". "ara generate" will be removed sometime in
the future so let's adjust it right away.

Change-Id: I31bff0a7e130c329da44b46506f5b12fa8d6deb8
Closes-Bug: #1665746

tools/deploy_aio.sh

@@ -23,7 +23,7 @@ function copy_logs {
 
     # NOTE(SamYaple): Fix permissions for log extraction in gate
     chmod -R 777 /tmp/logs/kolla /tmp/logs/kolla_configs /tmp/logs/system_logs
-    ara generate /tmp/logs/playbook_reports/
+    ara generate html /tmp/logs/playbook_reports/
 }
 
 function sanity_check {