Enable Gradle dependency verification

[chenxiaolong]

The verification file is a bit annoying to generate/update due to a couple issues, but I still think this is worthwhile to enable to protect from compromised dependencies, especially with BCR having system app permissions.

Issues:

• https://github.com/gradle/gradle/issues/19228 - When dependencies are already cached, generating the verification file will sometimes result in missing entries.
• The documented ./gradlew --write-verification-metadata sha512 help command isn't sufficient to grab all dependencies. The actual APK build and tests need to be run as part of the command to ensure all dependencies are added.

To generate the file in this PR, I ran:

./gradlew --stop
rm -r ~/.gradle/caches
./gradlew --write-verification-metadata sha512 --no-daemon build zipDebug -x assembleRelease