[native] Call goBackToPrompt when registration fails in FullscreenSIWEPanel

Summary:
When something goes wrong during registration, we always show an Alert in registrationServerCall.

When registrationServerCall is called from FullscreenSIWEPanel, we want to call goBackToPrompt if it fails, after the user acknowledges the prompt.

Depends on D12082

Test Plan:

1. Force a client_version_unsupported failure by hardcoding it in keyserver/src/session/version.js
2. Disable enableNewRegistrationMode
3. Enable usingCommServicesAccessToken
4. Try FullscreenSIWEPanel with a wallet that hasn't been registered before
5. Verify that goBackToPrompt is called after acknowledging the Alert

Reviewers: inka

Reviewed By: inka

Subscribers: tomek

Differential Revision: https://phab.comm.dev/D12083