Fix for: Generated suggested strong passwords not autofill'd for certain apps.

Context:
This bug mainly occurs in multi page auth scenarios such as:
Page/Screen 1:
username field
Page/Screen 2:
password + confirm password field

For the above:
On completion of page 1, the session is committed and a new session is kicked off. However, the new session (for page 2) will now contain the username field from the prev session (merged) along with the two new fields (pw + confirm pw).

As a result, a fill req + fill response (triggered by generate strong pw) will now contain (username, pw, confirm pw) in the returned dataset. However, this will fail as (username) is in the returned dataset but it is not part of the current screen.

Fix: The fix here is to ignore any fields (in the fillresponse) that don't belong to the current session. The previously submitted gms fix will be reverted (separately) as well to not conflict with this change

Test + confirmed that w/ flag (fill_fields_from_current_session_only=True) enabled the issue is no longer observed.

Flag: fill_fields_from_current_session_only
Bug: 270722825
Bug: 289585475
Test: atest CtsAutoFillServiceTestCases
Change-Id: I05b5d841ea99d7738b306ba4acfb577827da71a8