* Automatically derive active protos target used in proto_format.sh from the packages with files
annotated as active.
* Replace some sites with hardcoded v2/v3 with active/next_major_version_candidate.
* Move //docs:BUILD to //versioning:BUILD in API tree. This has already ceased to be used directly
in the docs build, so this makes things a bit clearer.
Risk level: Low (API tooling and build only)
Testing: fix_format (mostly idempotent)
Part of #10355.
Signed-off-by: Harvey Tuch <htuch@google.com>
Mirrored from https://github.com/envoyproxy/envoy @ 4403003b9c0888ce81606a2f45fcc1da126514e7
data-plane-api(CircleCI)