update usage strings for consistency

This updates the format of various usage strings to be more consistent
with other parts of the CLI.

- Use `[OPTIONS]` to indicate where command-specific options should be added
- Use `[SERVICE...]` to indicate zero-or-more services
- Remove some usage strings for specific options (e.g. `-e NAME=VAL`), as that
  option is part of the already mentioned `[OPTIONS]` and we don't provide usage
  for each possible option that can be passed.
- Remove `[--]`, which (I think) was needed for the Python implementation, but is
  a general feature to stop processing flag-options.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

docs/reference/docker_compose_pull.yaml

@@ -3,7 +3,7 @@ short: Pull service images
 long: |-
     Pulls an image associated with a service defined in a `compose.yaml` file, but does not start containers based on
     those images.
-usage: docker compose pull [SERVICE...]
+usage: docker compose pull [OPTIONS] [SERVICE...]
 pname: docker compose
 plink: docker_compose.yaml
 options: