Remove MODULE_LICENSE_APACHE2 from interfaces

Repositories containing third-party code need a METADATA and a
license_type. Repositories containing only first-party code no longer
need a MODULE_LICENSE_* file.

Bug: 68860345
Bug: 69058154
Bug: 151953481

Test: no code changes
Change-Id: I1b35928d82dfd8ac6429bf6a98f18a256fa6298c