Update gas limit to 36M instead, due to security concerns

[yawarasuuna]

As discussed here, here, and here , due to security concerns, a 60 million gas limit might not be prudent , and right now it could lead to a full liveness attack on the network until this issue is fixed. All client devs are already working on a fix to it.

Instead, we could safely increase the gas limit to 36 million, a 20% increase, at least until Pectra goes live and further data is available to be analyzed.

[prestonvanloon]

Please see ACD 147 ethereum/pm#1211

The network gossip limits will not be raised until Pectra. Advertising 60M is a risk until after Pectra.

[nanexcool]

Yup, we're gonna suggest 36M as well, thanks for the PR!