@Test
    public void notApplicableWhenIgnoringUserPropertiesAndNotConfigured() {
        assumeThat(System.getenv("DOCKER_HOST")).isNull();

        Mockito
            .doReturn("autoIgnoringUserProperties")
            .when(TestcontainersConfiguration.getInstance())
            .getEnvVarOrProperty(eq("dockerconfig.source"), anyString());

        EnvironmentAndSystemPropertyClientProviderStrategy strategy = new EnvironmentAndSystemPropertyClientProviderStrategy();

        assertThat(strategy.isApplicable()).isFalse();
    }
Test that we can use Testcontainers configuration file to override settings. We assume that docker-java has test
coverage for detection of environment variables (e.g. DOCKER_HOST) and its own properties config file.
core/src/test/java/org/testcontainers/dockerclient/EnvironmentAndSystemPropertyClientProviderStrategyTest.java