Update manifest merger to 31.2.0-alpha08

JAVA_HOME=$ANDROID_BUILD_TOP/prebuilts/jdk/jdk11/linux-x86/   ./import-maven-artifacts.sh com.android.tools.build:manifest-merger:31.2.0-alpha08

Test: treehugger
Change-Id: I81638880a42e5b006136d41992ec7e76aea6ee43
236 files changed
tree: e098c04e2f27f05ba75b30ed0b8bae8b6651b82a
  1. com/
  2. Android.bp
  3. import-maven-artifacts.sh