### Description

Currently, the [`tryAuthenticateToken`](https://github.com/elastic/elasticsearch/blob/55088d154d1764a6d4fa8e9078bde9da1e9ff9a5/x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/TokenService.java#L458) method calls `decodeAndValidateToken` which ends up sending two `GetRequest` for the same token ID. First in [`decodeToken`](https://github.com/elastic/elasticsearch/blob/55088d154d1764a6d4fa8e9078bde9da1e9ff9a5/x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/TokenService.java#L602) and second in [`checkIfTokenIsValid`](https://github.com/elastic/elasticsearch/blob/55088d154d1764a6d4fa8e9078bde9da1e9ff9a5/x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/TokenService.java#L1977). The second call is unnecessary as we already fetched the access token in the first call, it's just simply dropped. We should refactor these two methods to avoid sending second get request just to validate the access token.
x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/TokenService.java
submitUnbatchedTask("install-token-metadata", new ClusterStateUpdateTask(Priority.URGENT) {
                    @Override
                    public ClusterState execute(ClusterState currentState) {
                        XPackPlugin.checkReadyForXPackCustomMetadata(currentState);
                        if (currentState.custom(TokenMetadata.TYPE) == null) {
                            return ClusterState.builder(currentState).putCustom(TokenMetadata.TYPE, getTokenMetadata()).build();
                        } else {
                            return currentState;
                        }
                    }
                    @Override
                    public void onFailure(Exception e) {
                        installTokenMetadataInProgress.set(false);
                        logger.error("unable to install token metadata", e);
                    }
                    @Override
                    public void clusterStateProcessed(ClusterState oldState, ClusterState newState) {
                        installTokenMetadataInProgress.set(false);
                    }
                });
            }
        }
    }
    /**
     * Package private for testing
     */
    void clearActiveKeyCache() {
        this.keyCache.activeKeyCache.keyCache.invalidateAll();
    }
    static final class KeyAndCache implements Closeable {