Rename stubs jar from '*-stubs.jar' to '*.jar' when importing artifacts.
(This was supposed to be part of b9868b1a58 but was lost in a rebase.)
Bug: 235578272
Test: manual: run finalize_sdk.py and inspect prebuilts/sdk/extensions
Change-Id: I93a3ef6f75a566ff5d0c525a15e2003fb7b890ed