Fix FCU avalanche issue

[SozinM]

we have issue that in some moments (when chain post L1 data) we get avalanche of FCU without attributes (1000s of them)
Because of this we have missing blocks, we need to fix the issue

[SozinM]

I've come up with an idea for a fix
We could create 2 type of Client (for builder and for l2)
One client would be for block building critical call (FCU with attrivutes, newPayload, getPayload). Another would serve only FCU without attributes.