A service top-level element equivalent for "docker run --label-file" argument

[swonky]

Description

The docker run command has a cli argument --label-file that allows you to pass a list of container labels using a line delimited file. It works much like the --env-file argument and its equivalent env_file compose element.

I can't find an equivalent compose element that can provide this functionality. My suggestion would be to implement something to the effect of a label_file service top-level element. It would be very helpful when compartmentalizing large compose files with many labels.