bug: rabin chunker errors when no options are passed

[SgtPooki]

calling rabin() throws an error, Error: please specify an average chunk size

https://github.com/ipfs/js-ipfs-unixfs/blob/b7a98f0e850bf488ba7430e90812ddb5f5c0c438/packages/ipfs-unixfs-importer/src/chunker/rabin.ts#L53-L55

options are all optional, and there is a default AVG chunk size, so we should not be erroring here, or we should have better enforced types.

[achingbrain]

Good spot, would you like to PR a quick fix?

[github-actions[bot]]

:tada: This issue has been resolved in version ipfs-unixfs-importer-v15.1.7 :tada:

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

Your semantic-release bot :package::rocket: