Auth errors not handled correctly during create survey flow

[gino-m]

loading-state.model.ts:1 ERROR Error: Uncaught (in promise): FirebaseError: [code=permission-denied]: Missing or insufficient permissions.
FirebaseError: Missing or insufficient permissions.
    at resolvePromise (zone.js:1265:35)
    at zone.js:1172:21
    at zone.js:1188:37
    at asyncGeneratorStep (asyncToGenerator.js:6:1)
    at _throw (asyncToGenerator.js:25:1)
    at _ZoneDelegate.invoke (zone.js:412:30)
    at Object.onInvoke (core.mjs:24210:33)
    at _ZoneDelegate.invoke (zone.js:411:56)
    at Zone.run (zone.js:169:47)
    at zone.js:1329:38

@os-micmec

Repro by clicking Ground logo at top-level.

[gino-m]

"Continue" started working once the permissions issue was fixed, but there is an underlying issue related to error handling - create survey flow still shows for unauthenticated users or when user doesn't have permission to write.

[gino-m]

@DaoyuT FYI related to #931.