tests: Bluetooth: disable optimizations in unit test

Very very weird behavior.

Deleting the `options & BT_LE_ADV_OPT_USE_NRPA` branch in
`id.c:bt_id_set_adv_own_addr` makes the test pass. But add a log in that
branch, and you'll see that we never take it in the UT binary..

I don't have time for this, maybe some compiler guru or C language
lawyer can look at that decompiled function and figure out the root
cause.

Someone should also really fix the Bluetooth unit tests and make them
run on any Bluetooth related PR. Also nightly.

Signed-off-by: Jonathan Rico <jonathan.rico@nordicsemi.no>