If the endpoint is secured by a bearer access token verification mechanism then, when no token is provided, a debug log message should inform users about it.
It is already done in `quarkus-oidc` [here](https://github.com/quarkusio/quarkus/blob/main/extensions/oidc/runtime/src/main/java/io/quarkus/oidc/runtime/BearerAuthenticationMechanism.java#L30).
But `quarkus-smallrye-jwt` does not log the same message, so this PR adds it there as well.