Switch to dynamic Stripe3DS2.xcframework for SPM

[davidme-stripe]

Summary

• Switch to a dynamic version of Stripe3DS2.xcframework when using SPM, and stop enforcing that SPM builds Stripe as a dynamic framework.
• Use the static .xcframework for Carthage and manual installations, fixing a bug with Carthage and manual installation when using Catalyst. Also includes the fix for Mac Catalyst slice fails on Xcode 12 during 3DS2 transaction with unrecognized selector: [UIColor _stds_labelColor] #1649.
• Continuing using libStripe3DS2.a for Cocoapods until 1.10 is released, which will fix support for .xcframeworks.
• Fix Jazzy settings to ignore the InternalFrameworks/ headers.

Motivation

Many issues with SPM + type: .dynamic frameworks.
#1650, #1651, #1658, and #1670.

Testing

Using test apps on sim and device with SPM and manual installation.