aya/xtask
Tamir Duberstein 6ac1320707
integration-test: build "fake" by default
Use the environment variable AYA_BUILD_INTEGRATION_BPF to indicate to
the build script that it should *actually* build bpf, otherwise emitting
empty files.

This allows metadata builds to skip costly build steps without
sacrificing ergonomics; all compile-time tools such as cargo clippy work
out of the box.

Cargo even gives each of these builds (depending on the value of the
environment variable) its own cache key, so they do not invalidate each
other when the user alternates between metadata and real builds.

This allows the lint action to move out of the VM.
..
src integration-test: build "fake" by default
Cargo.toml xtask: Standardize command logging