Constant polkadot_runtime_parachains::paras::MAX_PARA_HEADS

pub const MAX_PARA_HEADS: usize = 1024;

This is intermediate “fix” for this issue: https://github.com/paritytech/polkadot-sdk/issues/4737

It does not actually fix it, but makes the worst case better. Without that limit someone could completely DoS the relay chain by registering a ridiculously high amount of paras. With this limit the same attack could lead to some parachains ceasing to being able to communicate via offchain XCMP. Snowbridge will still work as it only cares about BridgeHub.