@Override
        public boolean equals(Object o) {
            if (this == o) {
                return true;
            }

            if (o == null || getClass() != o.getClass()) {
                return false;
            }

            VerificationKeyResolverKey that = (VerificationKeyResolverKey) o;
            return configs.equals(that.configs) && moduleOptions.equals(that.moduleOptions);
        }
<code>VkrKey</code> is a simple structure which encapsulates the criteria for different
sets of configuration. This will allow us to use this object as a key in a {@link Map}
to keep a single instance per key.
clients/src/main/java/org/apache/kafka/common/security/oauthbearer/OAuthBearerValidatorCallbackHandler.java