Fix Carthage Scheme issue.

[csauvage]

When building against Carthage, we have an issue with ITMS Transporter saying This bundle .../SwiftyMarkdown.framework is invalid. The Info.plist file is missing the required key: CFBundleVersion. Please find more information about CFBundleVersion at https://developer.apple.com/documentation/bundleresources/information_property_list/cfbundleversion"

@SimonFairbairn I assume your building the package using swift package CLI Command, maybe looking at this could help :

• https://danielsaidi.com/blog/2019/10/29/app-store-submission-fails-with-carthage-for-spm-generated-projects