Improve EL client diversity awareness

We currently have a "client diversity warning" on the page of selecting Prysm:
<img width="1069" alt="image" src="https://user-images.githubusercontent.com/9263930/173558443-4fb335b7-6a36-4029-89db-13499e1ed981.png">


Geth has a stronger supermajority in EL clients. It makes sense to add a warning to the page of selecting Geth too.
