Method names `createCredentialsOptions` and `getCredentialsOptions` are misleading

https://github.com/eclipse-vertx/vertx-auth/blob/f2fe95820b41db7da3afcc8a2028fedeb8b5ee8f/vertx-auth-webauthn4j/src/main/java/io/vertx/ext/auth/webauthn4j/WebAuthn4J.java#L64
https://github.com/eclipse-vertx/vertx-auth/blob/f2fe95820b41db7da3afcc8a2028fedeb8b5ee8f/vertx-auth-webauthn4j/src/main/java/io/vertx/ext/auth/webauthn4j/WebAuthn4J.java#L76

The names of these methods are misleading.
When placed side by side, `createCredentialsOptions` appears to be method that create `CredentialsOptions` and `getCredentialsOptions` appears to just return `CredentialsOptions`.
However, they actually create `PublicKeyCredentialCreationOptions` and `PublicKeyCredentialGetOptions`, respectively.

Since introducing a new module `vertx-auth-webauthn4j` is a good chance to make a breaking change from `vertx-auth-webauthn`, I think these methods should be renamed to `createPublicKeyCredentialCreationOptions` and `createPublicKeyCredentialGetOptions`.