How come in preseason 7 that the custom games won't bring bots anymore

Bots are actually still there, you just cannot use them on the new client. If you want a custom bot game (which I do frequently), just launch the legacy client.

If you look at the patch notes you will see that they are working on implementing bots, Just be patient

Don't worry about it just yet they plan on adding them into the new client it will just be a bit of time before this happens.