Add test for ACL state change on sub-device

Adds a unit test to verify that ACL connection state changes for sub-devices are correctly handled and dispatched. This covers the behavior modified by the removal of the sub-device check in `AclStateChangedHandler`.

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Original Change: ag/35256714
Test: passed ABTD tests http://go/forrest-run/L13000030017280691
Bug: 431235865
Flag: TEST_ONLY

Change-Id: Ia44f41e21654ba425243cb79abc8c46338df6c8a