volumes are not properly merged when using long format

[kadel]

Describe the bug

When using the long syntax for the volumes, they are not properly merged which results in the duplicated volumes.

#docker-compose.yaml
version: "3"
services:
  web:
    image: busybox
    command: ["/bin/busybox", "httpd", "-f", "-h", "/var/www/html", "-p", "8080"]
    ports:
      - 8080:8080
    volumes:
      - type: bind
        source: ./index.txt
        target: /var/www/html/index.html
        read_only: true
        bind:
          selinux: z
      - type: bind
        source: ./index.txt
        target: /var/www/html/index2.html
      - type: bind
        source: ./index.txt
        target: /var/www/html/index3.html
        read_only: true

# docker-compose.override.yaml
version: "3"
services:
  web:
    volumes:
      - type: bind
        source: ./override.txt
        target: /var/www/html/index.html
        read_only: true
        bind:
          selinux: "z"
      - type: bind
        source: ./override.txt
        target: /var/www/html/index2.html
        bind:
          selinux: "z"
      - type: bind
        source: ./override.txt
        target: /var/www/html/index3.html

result is

$ podman-compose -f docker-compose.yaml -f docker-compose.override.yaml config
services:
  web:
    command:
    - /bin/busybox
    - httpd
    - -f
    - -h
    - /var/www/html
    - -p
    - '8080'
    image: busybox
    ports:
    - 8080:8080
    volumes:
    - bind:
        selinux: z
      read_only: true
      source: ./index.txt
      target: /var/www/html/index.html
      type: bind
    - source: ./index.txt
      target: /var/www/html/index2.html
      type: bind
    - read_only: true
      source: ./index.txt
      target: /var/www/html/index3.html
      type: bind
    - bind:
        selinux: z
      read_only: true
      source: ./override.txt
      target: /var/www/html/index.html
      type: bind
    - bind:
        selinux: z
      source: ./override.txt
      target: /var/www/html/index2.html
      type: bind
    - source: ./override.txt
      target: /var/www/html/index3.html
      type: bind
version: '3'

When using the short syntax (./index.txt:/var/www/html/index.html:ro,z) it works as expected. Short syntax case is covered by tests (https://github.com/containers/podman-compose/tree/main/tests/integration/merge/volumes_merge) but long is not.

To Reproduce

1. create files docker-compose.yaml and docker-compose.override.yaml as specified in description
2. run podman-compose -f docker-compose.yaml -f docker-compose.override.yaml config

Expected behavior the resulting compose file should have only 3 volumes, with correctly overwritten source path.

Actual behavior the resulting compose file has 6 volumes, it incorrectly merges volumes from docker-compose and docker-compose.override together

Output

$ podman-compose version
podman-compose version 1.3.0
podman version 5.4.2

Environment:

• OS: Mac
• podman version: