Ideally, we would be able to run each yaml test with a different cluster setup, but that's currently limited by only supporting a single yaml test suite client. @mark-vieira suggested we may able to support multiple clients that have a method to filter which yaml tests are run. This would also be great for running the same tests under different cluster conditions (single node vs multi node, etc).
test/yaml-rest-runner/src/main/java/org/elasticsearch/test/rest/yaml/ESClientYamlSuiteTestCase.java
* Property that allows to blacklist some of the REST tests based on a comma separated list of globs
     * e.g. "-Dtests.rest.blacklist=get/10_basic/*"
     */
    public static final String REST_TESTS_BLACKLIST = "tests.rest.blacklist";
    /**
     * We use tests.rest.blacklist in build files to blacklist tests; this property enables a user to add additional blacklisted tests on
     * top of the tests blacklisted in the build.
     */
    public static final String REST_TESTS_BLACKLIST_ADDITIONS = "tests.rest.blacklist_additions";
    /**
     * Property that allows to control whether spec validation is enabled or not (default true).
     */
    private static final String REST_TESTS_VALIDATE_SPEC = "tests.rest.validate_spec";
    private static final String TESTS_PATH = "rest-api-spec/test";
    private static final String SPEC_PATH = "rest-api-spec/api";
    /**
     * This separator pattern matches ',' except it is preceded by a '\'.
     * This allows us to support ',' within paths when it is escaped with a slash.
     *
     * For example, the path string "/a/b/c\,d/e/f,/foo/bar,/baz" is separated to "/a/b/c\,d/e/f", "/foo/bar" and "/baz".
     *
     * For reference, this regular expression feature is known as zero-width negative look-behind.
     *
     */
    private static final String PATHS_SEPARATOR = "(?<!\\\\),";
    private static List<BlacklistedPathPatternMatcher> blacklistPathMatchers;
    private static ClientYamlTestExecutionContext restTestExecutionContext;
    private static ClientYamlTestExecutionContext adminExecutionContext;
    private static ClientYamlTestClient clientYamlTestClient;
    private final ClientYamlTestCandidate testCandidate;