testing/bat: upgrade to 0.12.1

Also:
- add options="net" to enable rootbld builds
- clang-dev and llvm-dev are used by onig_sys crate build-time
1 job for !64 with bat in 20 seconds (queued for 3 seconds)
detached
Status Job ID Name Coverage
  Lint
passed #726
x86_64 docker-alpine
lint

00:00:20