WL-1109. Currently the system is using org filters to tag zendesk
tickets. MITxPro uses both MITxPro and MITProfessionalX org filters
to pull courses from both orgs. This is causing multiple emails to
be sent from Zendesk as they are getting tagged with both
whitelabel_MITProfessionalX and whitelabel_MITxPRO. This fix changes
to using SITE_NAME instead.