### Description

The [Get API key information API](https://www.elastic.co/guide/en/elasticsearch/reference/master/security-api-get-api-key.html) can currently filter the returned keys by:
 * key id/name
 * keys owned by the calling user
 * keys owned by other users, by `realm_name` and `username`

Irrespective of the filtering used, both invalidated and expired (but not yet deleted) keys will be included in the response.
In the response, keys have the `invalidated` boolean property, as well as the `expiration` property that contains the UNIX timestamp past of which the key is no longer valid for authentication.

I propose we introduce a way for the API to support retrieving:
* only valid API keys (not return invalidated keys) - using a boolean request parameter
* keys not expired before a certain timestamp - using a timestamp parameter that defaults to "now" - also note that keys' experiation date is always checked against the local node's clock
x-pack/plugin/security/src/main/java/org/elasticsearch/xpack/security/authc/ApiKeyService.java
} else {
            if (apiKeyDoc.hash == null) {
                throw new IllegalStateException("api key hash is missing");
            }
            if (apiKeyAuthCache != null) {
                final AtomicBoolean valueAlreadyInCache = new AtomicBoolean(true);
                final ListenableFuture<CachedApiKeyHashResult> listenableCacheEntry;
                try {
                    listenableCacheEntry = apiKeyAuthCache.computeIfAbsent(credentials.getId(), k -> {
                        valueAlreadyInCache.set(false);
                        return new ListenableFuture<>();
                    });
                } catch (ExecutionException e) {
                    listener.onFailure(e);
                    return;
                }
                if (valueAlreadyInCache.get()) {
                    listenableCacheEntry.addListener(ActionListener.wrap(result -> {
                        if (result.success) {
                            if (result.verify(credentials.getKey())) {
                                
                                validateApiKeyTypeAndExpiration(apiKeyDoc, credentials, clock, listener);
                            } else {
                                listener.onResponse(
                                    AuthenticationResult.unsuccessful("invalid credentials for API key [" + credentials.getId() + "]", null)
                                );
                            }
                        } else if (result.verify(credentials.getKey())) { 
                            listener.onResponse(
                                AuthenticationResult.unsuccessful("invalid credentials for API key [" + credentials.getId() + "]", null)