Events’ indexes are incorrectly converted to bytes for use in Sparse Merkle Tree

[shuse2]

Expected behavior

index bytes should be computed correctly for large value for event

Actual behavior

this._index << EVENT_TOPIC_INDEX_LENGTH_BITS will overflow when index is greater than 2 ** 29

https://github.com/LiskHQ/lisk-sdk/blob/89e7504ef5eb6183aefe576a93be3d6052e56038/elements/lisk-chain/src/event.ts#L71-L89

Steps to reproduce

Add test which includes the index more than 2 ** 29

Which version(s) does this affect? (Environment, OS, etc...)

6.0.0-beta.2-