Opt out of predictive back

On Android 16 (and with targetSdk>=36), predictive back will be enabled by default if not explicitly specified otherwise in the Manifest. Therefore opting out to prevent regressions.

Bug: 376407910
Test: presubmit
Flag: EXEMPT precautionary measure to prevent regressions on Android 16
(cherry picked from https://googleplex-android-review.googlesource.com/q/commit:c572e735c89ec97a5f0de8eedff3301d4bfa0cb3)
Merged-In: Ie5ab175981f7054c8d69808cf2630fcb5b444bde
Change-Id: Ie5ab175981f7054c8d69808cf2630fcb5b444bde