Use `maybeGetSemaphoreSnarkArtifacts` from `@zk-kit/utils`

[sripwoud]

Once privacy-scaling-explorations/zk-kit#240 merges and the corresponding new @zk-kit/utils package is published, we can delete all that code
https://github.com/semaphore-protocol/semaphore/blob/main/packages/proof/src/get-snark-artifacts.browser.ts
https://github.com/semaphore-protocol/semaphore/blob/main/packages/proof/src/get-snark-artifacts.node.ts

and use maybeGetSemaphoreSnarkArtifacts instead

[sripwoud]

Please assign this to me ^^

[vplasencia]

Hey @sripwoud! Done. Thanks.