@Test
    void requestHeaderValueContainingCommaIsInterpretedAsASingleValue() throws IOException {
        JettyTestDriver driver = JettyTestDriver.newInstance(new RequestHeaderEchoingHandler("X-Foo"));
        driver.client().newGet("/")
                .addHeader("X-Foo", "bar,baz")
                .addHeader("X-Foo", "foobar")
                .execute()
                .expectStatusCode(is(OK))
                .expectContent(is("bar,baz\nfoobar\n"));
        assertTrue(driver.close());
    }
@author Oyvind Bakksjo
@author Simon Thoresen Hult
@author bjorncs
container-core/src/test/java/com/yahoo/jdisc/http/server/jetty/HttpServerTest.java