Is there some say to link a SPM only for one config?

Question

Firstly I have a project with 3 config: DEV, PRE and PRO and only one target. Secondly I have my business logic in a separated module. This module contains some files to mock server responses. The objective is that this files only can be inserted for DEV.

Right now I think that it is not possible adding a SPM depend on the config. The solution I have found would create two target in the SPM, one with the testing files and other without them. After I'll need to create two target in the main project but I dislike this idea.

i.e Package.swift:

// swift-tools-version:5.3

import PackageDescription

let package = Package(
    name: "MyLibrary",
    platforms: [
        .iOS(.v11)
    ],
    products: [
        .library(name: "MyLibrary", targets: ["MyLibrary"]),
        .library(name: "MyLibrary Dev", targets: ["MyLibraryDev"]),
    ],
    dependencies: [
        // some external dependencies
    ],
    targets: [
        .target(
            name: "MyLibrary",
            dependencies: []
        ),
        .target(
            name: "MyLibraryDev",
            dependencies: [
                "MyLibrary",
            ],
            resources: [.process("Resources/Testing")]
        ),
        .testTarget(
            name: "MyLibraryTests",
            dependencies: ["MyLibrary", "MyLibraryDev"]
        )
    ]
)

I want to find some way to link (automatic or manually with a build script) the correct library to each config.