Add auth type to BiometricPrompt.AuthenticationResult

Now that BiometricPrompt supports primary auth via device credential,
we want the high-level type of authentication used to be available to a
developer via the AuthenticationResult in onAuthenticationSucceeded.
Rather than include information about the strength of the biometric
sensor by reusing the existing Authenticators.Types constants, this
commit adds new integer constants that provide similar information but
at a lower level of granularity (device credential vs. biometric).

Test: atest com.android.server.biometrics
Test: atest com.android.systemui.biometrics
Test: Manually inspect new AuthenticationResult object on Pixel 3/4

Bug: 80525177
Bug: 141025588

Change-Id: Ic09ffdff995afe374f11721e6e777632de9ae867