Merging multiple compose files containing include in wrong order

[Psy-Kai]

Describe the bug

If you pass multiple compoe files (multiple -f) the files get merged in the wrong order.

This only happens if the file which includes other files are not at the last position.

To Reproduce

We need a project containing of multiple compose files like

/dev.yml
/dev/db.yml
/foo.yml

# /dev.yml
include:
  - ./dev/db.yml

# /dev/db.yml
services:
  db:
    image: ubuntu

# /foo.yml
services:
  db:
    image: debian

Steps to reproduce the behavior:

1. call `podman-compose -f dev.yml -f foo.yml config

Expected behavior
The service db should have image: debian.

Actual behavior
The service db should have image: debian.

Additional context

The problem is that includes files are just appended to the list of files. But it should be inserted into the files list after the current processing file!

So the file list looks like

[
  "/dev.yml", # first cmd parameter
  "/foo.yml", # second cmd parameter
  "/dev/db.yml" # the file included in /dev.yml
]

But it should look like

[
  "/dev.yml", # first cmd parameter
  "/dev/db.yml" # the file(s) included in /dev.yml
  "/foo.yml", # next cmd parameter
]

[Psy-Kai]

This bug prevents the usage of podman-compose with https://github.com/devcontainers/cli. The devcontainer-cli generates a temporary second compose file which should override some keys of the original compose file (especially the mentioned image key).

This bug relates loosely to #1301. Fixing this bug here is a 3 liner. But fixing #1301 seems to lead to a bigger rework of how the include spec got implemented.