Create a protocol (e.g. `DataContainer`) that `Foundation.Data`, `Swift.Array<UInt8>`, and `LowEnergyAdvertisingData` can conform to for data buffer usage. - [x] Create `DataContainer` protocol - [x] Adopt `DataContainer` in Bluetooth target - [x] Adopt `DataContainer` in BluetoothGAP target - [ ] Adopt `DataContainer` in BluetoothGATT target - [ ] Adopt `DataContainer` in BluetoothHCI target