Mandatory commitments only

[alistair-singh]

Adds the IsMandatory flag to SafeScanCommitmentResult. This is just appended to logging in this PR.

But I used this flag to skip signed commitments that are not mandatory in order to test parity paritytech/polkadot-sdk#3108 .

	if !result.IsMandatory {
		logEntry.Info("Skipped due to not mandatory commitment.")
		continue
	}

We do not need code changes to support the fix. Leaving the IsMandatory field in here because I think its useful for logging. In the future we could use it to save costs by limiting submissions to the light client to only mandatory commitments.

Resolves: SNO-842

[yrong]

+1

[vgeddes]

I would rather we go all the way and add a documented MandatoryCommitmentsOnly config setting. Otherwise this code is going to be forgotten about it.

[yrong]

We may not really need another config as it can be already achieved by setting

snowbridge/web/packages/test/config/beefy-relay.json

Line 8 in aab91ae

"update-period": 0

with a value big enough(i.e. more than blocks in an epoch).

[alistair-singh]

Addressed in a791b2a.

We can use the update-period but this is more explicit and is good for testing the mmr fix as well. Currently turning this setting on will fail untill we update from upstream polkadot-sdk. I tested this change with cherry-picking .

$ git cherry-pick e5bb11b008ca6c1b5a07cab94a2327538f3bf15c

I think this setting also works well with incentivizing beefy relayers. For instance, our relayer can run in a mode where it only sync's mandatory commitments (i.e. 1 commitment per epoch). And if there are pending messages and an incentive is provided by a user to speed up the transaction then it can sync the next commitment it sees.