Restoring unicode testcase

Signed-off-by: Joakim Erdfelt <joakim.erdfelt@gmail.com>

jetty-http2/http2-server/src/test/java/org/eclipse/jetty/http2/server/HTTP2ServerTest.java

@@ -390,8 +390,9 @@ public class HTTP2ServerTest extends AbstractServerTest
                 @Override
                 protected void service(HttpServletRequest request, HttpServletResponse response)
                 {
+                    // @checkstyle-disable-check : AvoidEscapedUnicodeCharactersCheck
                     // Invalid header name, the connection must be closed.
-                    response.setHeader("Euro_(%E2%82%AC)", "42");
+                    response.setHeader("Euro_(\u20AC)", "42");
                 }
             });