Integration test for QR code verification (#3439)
* Integration test for QR code verification
Followup to https://github.com/matrix-org/matrix-js-sdk/pull/3436: another
integration test, this time using the QR code flow
* Use Object.defineProperty, and restore afterwards
Apparently global.crypto exists in some environments
* apply ts-ignore
* remove stray comment
* Update spec/integ/crypto/verification.spec.ts
