### 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boolean property, as well as the `expiration` property that contains the UNIX timestamp past of which the key is no longer valid for authentication.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
public List<RoleDescriptor> parseRoleDescriptorsBytes(
        final String apiKeyId,
        BytesReference bytesReference,
        RoleReference.ApiKeyRoleType roleType
    ) {
        return parseRoleDescriptorsBytes(apiKeyId, bytesReference, roleType == RoleReference.ApiKeyRoleType.LIMITED_BY);
    }
    private List<RoleDescriptor> parseRoleDescriptorsBytes(
        final String apiKeyId,
        BytesReference bytesReference,
        final boolean replaceLegacySuperuserRoleDescriptor
    ) {
        if (bytesReference == null) {
            return Collections.emptyList();
        }
        List<RoleDescriptor> roleDescriptors = new ArrayList<>();
        try (
            XContentParser parser = XContentHelper.createParser(
                XContentParserConfiguration.EMPTY.withDeprecationHandler(new ApiKeyLoggingDeprecationHandler(deprecationLogger, apiKeyId)),
                bytesReference,
                XContentType.JSON
            )
        ) {
            parser.nextToken(); 
            while (parser.nextToken() != XContentParser.Token.END_OBJECT) {
                parser.nextToken(); 
                String roleName = parser.currentName();
                roleDescriptors.add(RoleDescriptor.parse(roleName, parser, false));
            }
        } catch (IOException e) {