UPDATE 13/03/20: It's good news for Warzone players, as it seems that game-breaking revive exploit has already been addressed by Infinity Ward.
Thanks to a playlist update rolled out last night, players should no longer be able to sit in the gas cloud reviving each other forever (something made easy with the help of perks). While Infinity Ward's tweet is somewhat vague, with a little gaswork it's almost certainly about the infinite revive perk found by players earlier this week.
Meanwhile, kill credits in Warzone will soon go to the player who downs an enemy rather than the person who lands the finishing blow. A tweet from co-design director Joe Cecot explained this “just missed release” but will be added in the next major update, which means you'll have to start getting your own kills instead of just hoovering up after your teammates.