Add id-token:write permissions to release-plz release job

[r-n-o]

From https://release-plz.dev/docs/github/quickstart#2-set-the-cargo_registry_token-secret

If you want to use trusted publishing, don't use the rust-lang/crates-io-auth-action action, and don't set the CARGO_REGISTRY_TOKEN secret (if you already use CARGO_REGISTRY_TOKEN, remove it from your workflow file entirely). release-plz implements the same crates-io API calls of the rust-lang/crates-io-auth-action action, and uses them to obtain a token when necessary.

Set id-token: write in the permissions of the job that runs release-plz release.

[ethankonk]

Are you planning on updating the rest of the workflow in a separate PR? Just wondering cuz I believe the CARGO_REGISTRY_TOKEN is still there

[r-n-o]

@ethankonk good catch! Pushed this up!