Update http-server-undertow/src/test/groovy/io/micronaut/servlet/unde…

…rtow/UndertowErrorSpec.groovy

Co-authored-by: Sergio del Amo <sergio.delamo@softamo.com>

http-server-undertow/src/test/groovy/io/micronaut/servlet/undertow/UndertowErrorSpec.groovy

@@ -42,7 +42,7 @@ class UndertowErrorSpec extends Specification {
         client.toBlocking().exchange("/errors/stream-immediate", String)
 
         then:
-        HttpClientResponseException ex = thrown(HttpClientResponseException)
+        HttpClientResponseException ex = thrown()
         ex.status == HttpStatus.INTERNAL_SERVER_ERROR
         ex.response.body.orElseThrow() == "Internal Server Error: Immediate error"
     }