chore(*): added TODOs for billing updates in all extensions pre-install files

[dackers86]

@kevinthecheung @karayu The text a small amount has been highlighted for removal in all extensions.

[i14h]

@karayu wdyt about this considering the AR change coming out next week?

[karayu]

Hey! We should remove this line altogether when @pavelgj turns AR live -- that's planned for this week

[dackers86]

Hi @karayu

I can make this update, just to confirm are we removing the entire line from the preinstalls? For example:

You will be charged a small amount (typically around $0.01/month) for the Firebase resources required by this extension (even if it is not used).

[karayu]

Yep! Though actually we should confirm with @pavelgj that it's rolled out

[dackers86]

The AR feature is to be rolled back. Moving to blocked for now.