### 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boolean property, as well as the `expiration` property that contains the UNIX timestamp past of which the key is no longer valid for authentication.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/test/java/org/elasticsearch/xpack/security/authc/ApiKeyServiceTests.java
final AuthenticationResult<User> authResult5 = future5.get();
        assertSame(AuthenticationResult.Status.SUCCESS, authResult5.getStatus());
        assertThat(authResult5.getMetadata().get(API_KEY_TYPE_KEY), is(type.value()));
        checkAuthApiKeyMetadata(metadata4, authResult5);
    }
    public void testWillInvalidateAuthCacheWhenDocNotFound() {
        ApiKeyService service = createApiKeyService(Settings.EMPTY);
        final ThreadContext threadContext = threadPool.getThreadContext();
        final String docId = randomAlphaOfLength(16);
        final String apiKey = randomAlphaOfLength(16);
        final ApiKey.Type type = randomFrom(ApiKey.Type.values());
        ApiKeyCredentials apiKeyCredentials = getApiKeyCredentials(docId, apiKey, type);
        service.getApiKeyAuthCache().put(docId, new ListenableFuture<>());
        assertNotNull(service.getApiKeyAuthCache().get(docId));
        SecurityMocks.mockGetRequest(
            client,
            SECURITY_MAIN_ALIAS,
            docId,
            new GetResult(
                INTERNAL_SECURITY_MAIN_INDEX_7,
                docId,
                UNASSIGNED_SEQ_NO,
                UNASSIGNED_PRIMARY_TERM,
                randomLongBetween(0, 9),
                false,
                null,
                null,
                null
            )
        );