Upgrade RevenueCat SDK to be able to test paywalls v2

[nyeu]

Upgrading the SPM version of the sample app to minimum version 5.16.0 to support paywalls v2

[RevenueCat-Danger-Bot]

	1 Error
🚫	Label the PR using one of the change type labels. If you are not sure which label to use, choose pr:other.

Label	Description
pr:feat	A new feature. Use along with pr:breaking to force a major release.
pr:fix	A bug fix. Use along with pr:force_minor to force a minor release.
pr:other	Other changes. Catch-all for anything that doesn't fit the above categories. Releases that only contain this label will not be released. Use along with pr:force_patch, or pr:force_minor to force a patch or minor release.
pr:RevenueCatUI	Use along any other tag to mark a PR that only contains RevenueCatUI changes
pr:next_release	Preparing a new release
pr:dependencies	Updating a dependency
pr:phc_dependencies	Updating purchases-hybrid-common dependency

Generated by 🚫 Danger

[tonidero]

Looks good! Thanks for updating this!

[ajpallares]

Good. Thanks!

[facumenzella]

nit: we should fix the version to a prevent unnecessary updates in the project 😢