Upgrade @metamask/polling-controller to version 16.0.0

A new major version of `@metamask/polling-controller`, 16.0.0, 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.

Search the dependency manifests for @metamask/polling-controller and inspect how its current version is used in the extension. Update the declaration to 16.0.0, then run the relevant project checks; done means the new version is installed without breaking the extension.

Written by the indexing model from the issue text.