Get-DbaServerAudit, return info if no audits found
Get-DbaServerAudit, return info if no audits found

Fixes #1605. Stylecop please watch if I got all.

wsmelton/dbatools,alevyinroc/dbatools,SirCaptainMitch/dbatools,Splaxi/dbatools,kozloski/dbatools,sqlpadawan/dbatools,dsolodow/dbatools