Support for swift package build plugins

[BrentMifsud]

It would be nice if this tool supported swift package plugins so we didn't have to use a build phase to run it.

Details here: https://github.com/apple/swift-package-manager/blob/main/Documentation/Plugins.md

[stevelandeyasana]

Great idea! Just to set expectations, we're unlikely to work on this ourselves, because we only run the tool once per week during our release process. But I'd happily help someone get a patch landed.

[BrentMifsud]

I can potentially look into this.

But this requires a binary target (see swiftgen's implementation as an example)

@stevelandeyasana would someone at Asana be able to set that up?