Zyra's plants needs to be more like Heimer's turrets when it comes to targeting

Pros: Plants will now target switch to enemy champions every time they walk within radius.

Cons: the enemy will complain how un-fun it is to lane against a Zyra support.

Solution: Plants die within one auto attack hit early game but plants will progressively gain health throughout the game.

Why do I think this is an issue: Every time my plants are spawned, they target the enemy champion first but as they leave their radius and walk back in, they ignore the enemy champion and focus on minions.

Why do I think it'll be an issue for the enemy when buffed: It'll be impossible for the ADC to properly farm. They'll constantly get harassed by the plants, dealing so much damage early game. However, with plants dying in one shot, there shouldn't be any complaint.