fix(bundler): do not skip updater bundle target if only a macOS DMG is generated

[AlexTMjugador]

What kind of change does this PR introduce?

• Bugfix
• Feature
• Docs
• New Binding issue #___
• Code style update
• Refactor
• Build-related changes
• Other, please describe:

Does this PR introduce a breaking change?

• Yes, and the changes were approved in issue #___
• No

Checklist

• When resolving issues, they are referenced in the PR's title (e.g fix: remove a typo, closes #___, #___)
• A change file is added if any packages will require a version bump due to this PR per the instructions in the readme.
• I have added a convincing reason for adding this feature, if necessary

Other information

As explained in #7189 (comment), this little change addresses recent, unintended behavior changes in how the updater bundle operates.

[amrbashir]

I think we only support updating .app on macOS, and so DMG should be ignored if it is the only macOS target specified. cc @lucasfernog

[AlexTMjugador]

As far as I know, DMGs are containers for .app bundles, so generating a DMG implies generating an .app bundle and it is technically possible to update an application that was installed from a DMG by replacing its .app. But I stumbled upon this on CI when updating Tauri, and I don't have a Mac to confirm, so please take this with a grain of salt!

[lucasfernog]

@AlexTMjugador you're right. Thanks for catching this and contributing!