Improve error handling in getServiceClassAuthOrigin

Enhance reliability by throwing a TypeError when a service key definition is missing.
It's common for a key to be missing and might require the developer that writes tests to provide a fake on that fits the examples used.

Key changes:
- Added a check for missing service key definitions in getServiceClassAuthOrigin.
- Throws a TypeError with a clear message if the key is not found.
- Guides devs to use an override if needed which is often.

services/test-helpers.js

@@ -187,6 +187,11 @@ function getServiceClassAuthOrigin(serviceClass, authOverride, configOverride) {
     return serviceClass.auth.authorizedOrigins
   } else {
     const mergedConfig = _.merge(runnerConfig, configOverride)
+    if (!mergedConfig.public.services[auth.serviceKey]) {
+      throw new TypeError(
+        `Missing service key defenition for ${auth.serviceKey}: Use an override if applicable.`,
+      )
+    }
     return [mergedConfig.public.services[auth.serviceKey].authorizedOrigins]
   }
 }