lp1777677 Security tweaks

lp1777677 Security tweaks

- Refactor test notification API to check if requestor
is user,and if not, then check if requestor has
permissions to view users at target user's home ou.
- Change event_def_type references to "hook"
- Separate out sendTestEmail and sendTestSMS functions
in frontend to prevent potential misuse of functionality.

Signed-off-by: Kyle Huckins <khuckins@catalyte.io>
Signed-off-by: Terran McCanna <tmccanna@georgialibraries.org>
Signed-off-by: Chris Sharp <csharp@georgialibraries.org>
Signed-off-by: Galen Charlton <gmc@equinoxinitiative.org>