Revert "syslog_drain_url is added to service_instances, credentials are now optional"

This reverts commit 500f245dc9abc1a566c34d3d2fc4d5cf9694cc1c.

This gets the build pipline green again.
Revert "wip on adding syslog_drain_url"

This reverts commit d32ed57a478606d331fd3d4025c0fc5d004f38a2.

another revert to fix the pipeline, this was work for syslogdrain url on
service_instances