Add missing verification metadata entries

This fixed Gradle build errors for me on macOS

> Task :app:processBasicDebugResources FAILED
Execution failed for task ':app:processBasicDebugResources'.
> Dependency verification failed for configuration ':app:_internal_aapt2_binary'
  One artifact failed verification: aapt2-3.6.3-6040484-osx.jar (com.android.tools.build:aapt2:3.6.3-6040484) from repository maven
  If the artifacts are trustworthy, you will need to update the gradle/verification-metadata.xml file by following the instructions at https://docs.gradle.org/6.4.1/userguide/dependency_verification.html#sec:troubleshooting-verification

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

Generated this metadata by running:

./gradlew --write-verification-metadata sha256 help

as mentioned in Gradle docs at https://docs.gradle.org/6.4.1/userguide/dependency_verification.html#sec:bootstrapping-verification