Bsim: Bluetooth: Mesh: Rename/refactor `send_ra`

Renames `bt_mesh_test_send_ra` to `bt_mesh_test_send_data` and changes
the corresponding callback funciton as it is used outside of the replay
attack tests, and can be used to send custom data. The function is
extended to accept a UUID parameter to allow sending data to virtual
addresses.

Signed-off-by: Håvard Reierstad <haavard.reierstad@nordicsemi.no>