Added DefaultSPM flag and conditionally rendered card details label and default checkbox

[joyceqin-stripe]

Summary

Motivation

Testing

Changelog

[github-actions]

⚠️ Missing Translations
The following strings have been uploaded to Lokalise but are not yet translated.

Card details cannot be changed., Manage card, Your card has expired.

If it's okay for these strings to be unlocalized in master (e.g. this is for an unshipped feature), add the label ship without translations to acknowledge that there are missing translations. Otherwise, wait until translations are available in Lokalise and re-run this job.

New strings are localized on a weekly basis and are downloaded as part of the release process. For more details on how to localize a string, you can refer to this link.

[github-actions]

🚨 New dead code detected in this PR:

String+Localized.swift:118 warning: Property 'update' is unused
CustomerSavedPaymentMethodsCollectionViewController.swift:85 warning: Property 'defaultSPMNavigation' is assigned, but never used

Please remove the dead code before merging.

If this is intentional, you can bypass this check by adding the label skip dead code check to this PR.

ℹ️ If this comment appears to be left in error, double check that the flagged code is actually used and/or make sure your branch is up-to-date with master.