Handle intent returning multiple results at once

[sebdeveloper6952]

Quoting greenart7c3: "there's also some flags for the intent to return multiple results at once"

https://github.com/vitorpamplona/amethyst/blob/db3824c3c71dadb8d101ea2ba16e4bca50532de0/quartz/src/main/java/com/vitorpamplona/quartz/signers/ExternalSignerLauncher.kt#L215

https://github.com/vitorpamplona/amethyst/blob/db3824c3c71dadb8d101ea2ba16e4bca50532de0/quartz/src/main/java/com/vitorpamplona/quartz/signers/ExternalSignerLauncher.kt#L112