ash-app-pay: Fix cashApp not destroyed on unmount

[testerez]

Your checklist for this pull request

🚨Please review the guidelines for contributing to this repository.

• [ ] Make sure you are requesting to pull a topic/feature/bugfix branch (right side). Don't request your master!
• [x] Make sure you are making a pull request against the main branch (left side). Also you should start your branch off our main.
• [ ] Check the commit's or even all commits' message styles matches our requested structure.
• [ ] Check your code additions will fail neither code linting checks nor unit test.

Description

Please describe your pull request and add all the information and images that you need.

🧡 Thank you!

[testerez]

replaced by: https://github.com/weareseeed/react-square-web-payments-sdk/pull/100