java_sdk_library supports test as another API scope

For each java_sdk_library module, three (possibly different) stubs libs
are created.

*.stubs: public APIs only
*.system.stubs: public APIs + @SystemApi
*.test.stubs: public APIs + @TestApi

Depending on the sdk_version (or LOCAL_SDK_VERSION) of the calling
module, stubs lib of the corresponding api scope is linked.

Bug: 77575606
Test: m -j
Change-Id: I1437c64460914dbfc349dbc31d6f3ef090f541e3