Documentation update

[drupol]

Hello,

I think the custom service (https://github.com/juspay/services-flake/blob/main/doc%2Fcustom-service.md) examples are currently broken, when using the example 'as-is', it complains about the duplicate attribute "enabled".

Removing it fixed the problem.

[shivaraj-bh]

Is it while adding multi-instance service:

services-flake/doc/custom-service.md

Lines 88 to 108 in 00adb75

	```nix
	{ config, lib, name, pkgs, ... }:
	{
	options = {
	enable = lib.mkEnableOption "Enable ${name} service";
	package = lib.mkPackageOption pkgs "hello" { };
	message = lib.mkOption {
	type = lib.types.str;
	default = "Hello, world!";
	description = "The message to be displayed";
	};
	};
	config = {
	outputs.settings = {
	processes.${name} = {
	command = "${lib.getExe config.package} --greeting='${config.message}'";
	};
	};
	};
	}
	```

?

That is because we add it by default in the multiService library function:

services-flake/nix/lib.nix

Line 18 in 00adb75

enable = lib.mkEnableOption "Enable the ${service}.<name> service";

I will update the doc.