Update predictive back progress interpolator

Bug: 332512902
Flag: ACONFIG com.android.systemui.predictive_back_sysui TRUNKFOOD
Test: Manual, i.e. analysing screenrecordings and verify that there are no more animation jumps at the start/end of the back animations
Change-Id: I99b13199032f7098fedb1cbd02cfe478d6fbb1f7
2 files changed