### 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boolean property, as well as the `expiration` property that contains the UNIX timestamp past of which the key is no longer valid for authentication.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 ApiKeyDoc updatedApiKeyDoc = ApiKeyDoc.fromXContent(
                XContentHelper.createParser(XContentParserConfiguration.EMPTY, BytesReference.bytes(builder), XContentType.JSON)
            );
            assertEquals(oldApiKeyDoc.docType, updatedApiKeyDoc.docType);
            assertEquals(oldApiKeyDoc.type, updatedApiKeyDoc.type);
            assertEquals(oldApiKeyDoc.name, updatedApiKeyDoc.name);
            assertEquals(oldApiKeyDoc.hash, updatedApiKeyDoc.hash);
            assertEquals(oldApiKeyDoc.expirationTime, updatedApiKeyDoc.expirationTime);
            assertEquals(oldApiKeyDoc.creationTime, updatedApiKeyDoc.creationTime);
            assertEquals(oldApiKeyDoc.invalidated, updatedApiKeyDoc.invalidated);
            assertEquals(newVersion.id, updatedApiKeyDoc.version);
            final var actualUserRoles = service.parseRoleDescriptorsBytes(
                "",
                updatedApiKeyDoc.limitedByRoleDescriptorsBytes,
                RoleReference.ApiKeyRoleType.LIMITED_BY
            );
            assertEquals(newUserRoles.size(), actualUserRoles.size());
            assertEquals(new HashSet<>(newUserRoles), new HashSet<>(actualUserRoles));
            final var actualKeyRoles = service.parseRoleDescriptorsBytes(
                "",
                updatedApiKeyDoc.roleDescriptorsBytes,
                RoleReference.ApiKeyRoleType.ASSIGNED
            );
            if (changeKeyRoles == false) {
                assertEquals(
                    service.parseRoleDescriptorsBytes("", oldApiKeyDoc.roleDescriptorsBytes, RoleReference.ApiKeyRoleType.ASSIGNED),
                    actualKeyRoles
                );
            } else {
                assertEquals(newKeyRoles.size(), actualKeyRoles.size());