Launch multiple biometric enrollment when no biometric is enrolled

When a user clicks the biometric item in the Device unlock page and no
biometric is enrolled:
- Fingerint clicked: Launch fingerprint enroll then face enroll.
- Face clicked: Launch face enroll then fingerprint enroll.

Bug: 370940762
Test: atest FaceSafetySourceTest FingerprintSafetySourceTest
Flag: com.android.settings.flags.biometrics_onboarding_education
Change-Id: I874b96a75ec0c126ae1674bb6ab220a0a8533fcd