Remove use of `imp` for python 3.12+ upgrade am: 3682816e6b

Original change: https://android-review.googlesource.com/c/platform/external/libchrome/+/3443484

Change-Id: I9dd88965f3956407d61333f18f375853173cdeff
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>