Default `ignore` can be accidentally overridden in `packagerConfig`

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Electron Forge version

6.0.5

Electron version

v22.2.0

Operating system

macOS 13.4.1

Last known working Electron Forge version

No response

Expected behavior

Specifying an ignore option in packagerConfig should not replace any default options (unless the ignore option is a function, as per electron-packager's standard behaviour).

Actual behavior

If ignore is not specified in packagerConfig, then it defaults to [/^\/out\//g]. Setting ignore to any other value silently overrides this default.

As a consequence of this, the packager fails to remove the out directory.

For me, this results in the following crash:

An unhandled rejection has occurred inside Forge:
Error: Detected file "Contents/Resources/app/out/<MY APP>-darwin-arm64/<MY APP>.app/Contents/Frameworks/Electron Framework.framework/Versions/A/Electron Framework" that's the same in both x64 and arm64 builds and not covered by the x64ArchFiles rule: "undefined"
at exports.makeUniversalApp (<APP ROOT>/node_modules/@electron/universal/dist/cjs/index.js:101:27)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5)
    at async packageUniversalMac (<APP ROOT>/node_modules/electron-packager/src/universal.js:56:3)
    at async Promise.all (index 0)
    at async packager (<APP ROOT>/node_modules/electron-packager/src/index.js:204:20)

Steps to reproduce

I'm testing this by placing a console.log(opts.ignore) statement at the top of the userPathFilter function in node_modules/electron-packager/src/copy-filter.js.

Additional information

No response

electron / forge