Adding flag com.android.server.telecom.flags.end_session_improvements to bp1a. Bug: 370349160 Test: EXEMPT flagging Flag: com.android.server.telecom.flags.end_session_improvements (cherry picked from https://googleplex-android-review.googlesource.com/q/commit:990d2567074d7d453828cf9c36dab4d58800f272) Merged-In: Ibdd13b7626ddce87512b6b3ecb0a8b23547109cc Change-Id: Ibdd13b7626ddce87512b6b3ecb0a8b23547109cc