Fix nullable headset manager permission

[chandrabezzo]

Fix issue about

asset_audio_player/android/src/main/kotlin/com/github/florent37/assets_audio_player/stopwhencall/HeadsetManager.kt:93:53 Only safe (?.) or non-null asserted (!!.) calls are allowed on a nullable receiver of type Array<(out) String!>?

[✓] Flutter (Channel stable, 3.24.5, on macOS 15.3.1 24D70 darwin-arm64, locale en-ID)
[✓] Android toolchain - develop for Android devices (Android SDK version 35.0.1)
[✓] Xcode - develop for iOS and macOS (Xcode 16.2)
[✓] Chrome - develop for the web
[✓] Android Studio (version 2024.2)
[✓] Connected device (3 available)
! Error: Browsing on the local area network for SHDA0085. Ensure the device is unlocked and attached with a cable or associated with the same local area network
as this Mac.
The device must be opted into Developer Mode to connect wirelessly. (code -27)
[✓] Network resources

• No issues found!

[chandrabezzo]

For temporary usage, you can implement dependency like this

assets_audio_player:
    git:
      url: https://github.com/chandrabezzo/asset_audio_player
      ref: fix/android/headset-manager