Check if any of the data columns are slashable before publishing

[jimmygchen]

Description

When publishing a block, we check if any of the block and blobs are slashable here:

lighthouse/beacon_node/http_api/src/publish_blocks.rs

Lines 540 to 547 in ed7cd3b

	/// Check if any of the blobs or the block are slashable. Returns `BlockError::Slashable` if so.
	fn check_slashable<T: BeaconChainTypes>(
	chain_clone: &BeaconChain<T>,
	blobs_opt: &Option<BlobSidecarList<T::EthSpec>>,
	block_root: Hash256,
	block_clone: &SignedBeaconBlock<T::EthSpec, FullPayload<T::EthSpec>>,
	log_clone: &Logger,
	) -> Result<(), BlockError> {

We need to add the equivalent check for data column sidecars here too.

[michaelsproul]

I was kind of looking at this in the context of:

• Lenient duplicate checks on HTTP API for block publication #5574

Didn't impl it yet though

[jimmygchen]

I'm actually wondering if it's necessary to pass blobs / data columns to this function, because the block headers are derived from the block, so it seems redundant?