Remove support for generating versioned snapshots

Previously, the code for selecting specific versions of sdk snapshots
was removed (along with the uses_sdks property). That makes versioned
snapshots useless so this change removes all the code and tests that
generated those versioned snapshots.

Bug: 232546567
Test: m nothing
      packages/modules/common/build/mainline_modules_sdks.sh
Change-Id: Ib6d1b72bc8399fbb39075494ae37da92f4b28d03