REST Assured with plain/text response body

dependencies {
    testImplementation 'io.rest-assured:json-path:4.2.0'
    testImplementation 'io.rest-assured:xml-path:4.2.0'
    testImplementation 'io.rest-assured:kotlin-extensions:4.2.0'
    testImplementation 'io.rest-assured:spring-mock-mvc:4.2.0'
    testImplementation group: 'io.rest-assured', name: 'rest-assured', version: '4.2.0'
    testImplementation ('org.springframework.boot:spring-boot-starter-test') {
        exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
    }
}

test {
    useJUnitPlatform()
}

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

@RestController
public class PingController {

    @GetMapping("/ping")
    public String pong() {
        return "pong";
    }
}

import io.restassured.RestAssured;
import io.restassured.parsing.Parser;
import org.junit.jupiter.api.Test;

import static io.restassured.module.mockmvc.RestAssuredMockMvc.given;
import static org.hamcrest.CoreMatchers.equalTo;

public class MockMvcTest {

    @Test
    public void testMockMvcGetPlainText() {
        RestAssured.registerParser("text/plain", Parser.TEXT);  (1)
        given().standaloneSetup(new PingController())
                .when().get("/ping")
                .then().assertThat()
                    .statusCode(200)
                    .body(equalTo("pong"));     (2)
    }
}