Fix missing teamkill event on instakill

[MatthiasKunnen]

When a player got instakilled, due to large caliber or during grayed-out stage after revival, the teamkill event was not triggered.

Example from the logs:

[2021.10.31-00.38.35:319][ 83]LogSquad: Player:Victim ActualDamage=900.000000 from Attacker caused by BP_BTR82A_RUS_2A72_AP_C_2147479210
[2021.10.31-00.38.35:319][ 83]LogSquadTrace: [DedicatedServer]ASQSoldier::Die(): Player:Victim KillingDamage=900.000000 from BP_PlayerController_C_2147481608 caused by BP_BTR82A_RUS_2A72_AP_C_2147479210

[Thomas-Smyth]

After removing the teamkill changes and testing this should be ready to merge.