2.17.3 — a relative compose file label is resolved, not given up on

One fix, from @LeeNX's report in #65.

Fixed

• A Compose stack whose file label is relative is no longer rebuilt as standalone. Docker records the compose file as com.docker.compose.project.config_files, usually as an absolute path — but a label written as plain compose.yml turns up in the wild. Docksentry checked it against its own working directory, which inside a container is /app, so the file was never found and the update dropped silently into the standalone docker run recreate. That path rebuilds the container from its inspect data and can lose the healthcheck, which is the failure that was reported.

  A relative label is now resolved against com.docker.compose.project.working_dir, which Docker records absolute beside it. An absolute label, or a container with no working_dir, behaves exactly as before.