Cleanup: removal flags

    1. com.android.internal.telephony.flags.get_group_id_level2 flag
    2. com.android.internal.telephony.flags.action_sim_preference_settings flag and references

Bug: b/423931764, b/423964404
Test: atest
Flag: EXEMPT (remove flag)
Change-Id: I1e39bef9517b274a42548284d2f8909ad7e97c91