Reproducible build fails because of missing `fts-dev`

See for example https://gitlab.torproject.org/tpo/core/arti/-/jobs/263340, where we hit this error:

+ apk add bash cmake patch clang libc-dev libxml2-dev openssl-dev fts-dev build-base python3 bsd-compat-headers xz
ERROR: unable to select packages:
  fts-dev (no such package):
    required by: world[fts-dev]

It looks like fts-dev is some kind of a workaround for functionality that musl-libc doesn't have. Is it no longer there because musl-libc has this functionality now?