kubo and transmission modules conflict on wmem_max

[lordcirth]

Describe the bug

Attempting to upgrade from 22.05 to 23.11, the kubo and transmission modules have a conflict:

error: The option `boot.kernel.sysctl."net.core.wmem_max"' is defined multiple times while it's expected to be unique.

       Definition values:
       - In `/nix/store/9fpv0kjq9a80isa1wkkvrdqsh9dpcn05-source/nixos/modules/services/network-filesystems/kubo.nix': 2500000
       - In `/nix/store/9fpv0kjq9a80isa1wkkvrdqsh9dpcn05-source/nixos/modules/services/torrent/transmission.nix': "1048576"
       Use `lib.mkForce value` or `lib.mkDefault value` to change the priority on any of these definitions.
(use '--show-trace' to show detailed location information)

Steps To Reproduce

Steps to reproduce the behavior:

1. Enable services.kubo and services.transmission on 23.11
2. nixos-rebuild build

Expected behavior

An error-free build

Notify maintainers

@fpletz @astsmtl @vcunat @wizeman

Metadata

Please run nix-shell -p nix-info --run "nix-info -m" and paste the result.

$ nix-shell -p nix-info --run "nix-info -m"
 - system: `"x86_64-linux"`
 - host os: `Linux 5.15.85, NixOS, 22.05 (Quokka), 22.05.20230531.380be19`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.9.1`
 - channels(root): `"nixos-22.05"`
 - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos`

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[lordcirth]

Metadata after disabling transmission and upgrading:

$ nix-shell -p nix-info --run "nix-info -m"
 - system: `"x86_64-linux"`
 - host os: `Linux 6.1.82, NixOS, 23.11 (Tapir), 23.11.20240328.219951b`
 - multi-user?: `yes`
 - sandbox: `yes`
 - version: `nix-env (Nix) 2.18.1`
 - channels(root): `"nixos-22.05"`
 - nixpkgs: `/nix/var/nix/profiles/per-user/root/channels/nixos`