Upgrade @metamask/transaction-pay-controller to version 20.0.0

A new major version of `@metamask/transaction-pay-controller`, 20.0.0, is now available. This issue has been assigned to you and your team because you code-own this package in the `core` repo. If this package is present in this project, please prioritize upgrading it soon to unblock new features and bugfixes.

The payload names no file or test; start by locating the dependency declaration for @metamask/transaction-pay-controller in the metamask-mobile project. Confirm whether the package is present, update it to 20.0.0, and run the relevant project checks to verify the upgrade.

Written by the indexing model from the issue text.