[BluetoothMetrics] This covers the case for Direct LE-ACL Connection

Success Rate as per go/bluetooth-le-connection-metrics.

Unit Tests:
- Successful
- Failure
- Timeout
- Cancellation

Test: atest bluetooth_test_gd_unit:LEConnectionMetricsRemoteDeviceTest --host
Bug: 268252025
Change-Id: I918e999207d4d54248aa04e72eacff90e0f6ab50