Copy system_other.img to target_files.zip

Similar to https://r.android.com/3489814, this adds an additional rule
in systemOtherImage to create a hermetic version of system_other.img
with pinned timestamps. This information will be provided to
android_device via super_image.

block_list information is not implemented for system_other to match the
make behavior

Test: Built the soong built target_files.zip locally
Bug: 385383524
Change-Id: I4cbb4f8a5380203eaef846b3d8a56eb7791f8a34