feat: upgrade zerokit in @waku/rln

[weboko]

Update rln to use latest version of zerokit, load the WASM, and use it to generate credentials

Use the package in rln.waku.org to generate credentials in the browser

Validate that the generated credentials can be used to run an nwaku node and participate in relay/lightpush

[weboko]

@adklempner to add description