[JENKINS-53863] - Update JTH to 2.41.1 and enable testing with JDK 11

Jenkinsfile

@@ -17,7 +17,7 @@ properties([buildDiscarder(logRotator(numToKeepStr: '50', artifactNumToKeepStr:
 
 // see https://github.com/jenkins-infra/documentation/blob/master/ci.adoc for information on what node types are available
 def buildTypes = ['Linux', 'Windows']
-def jdks = [8]
+def jdks = [8, 11]
 
 def builds = [:]
 for(i = 0; i < buildTypes.size(); i++) {

pom.xml

@@ -760,5 +760,16 @@ THE SOFTWARE.
         <failIfNoTests>false</failIfNoTests>
       </properties>
     </profile>
+    <profile>
+      <id>jdk11</id>
+      <properties>
+        <!-- TODO: https://issues.jenkins-ci.org/browse/JENKINS-53788 (JDK11 issue on CI) -->
+        <doclint>none</doclint>
+        <maven.javadoc.skip>true</maven.javadoc.skip>
+      </properties>
+      <activation>
+        <jdk>11</jdk>
+      </activation>
+    </profile>
   </profiles>
 </project>

src/findbugs/findbugs-excludes.xml

@@ -10,6 +10,9 @@
       <Bug pattern="UMAC_UNCALLABLE_METHOD_OF_ANONYMOUS_CLASS"/>
       <!-- TODO: It's a real issue, but the code is flooded by it right now-->
       <Bug pattern="DM_DEFAULT_ENCODING"/>
+      <!-- TODO: Remove once we migrate to SpotBugs with full Java support (JENKINS-53720)-->
+      <!-- This check works unreliably on JDK 11 which tries doing some code generation for annotated fields-->
+      <Bug pattern="RCN_REDUNDANT_NULLCHECK_WOULD_HAVE_BEEN_A_NPE"/>
     </Or>
   </Match>
 </FindBugsFilter>

test/pom.xml

@@ -53,7 +53,7 @@ THE SOFTWARE.
     <dependency>
       <groupId>${project.groupId}</groupId>
       <artifactId>jenkins-test-harness</artifactId>
-      <version>2.36</version>
+      <version>2.41.1</version>
       <scope>test</scope>
       <exclusions>
         <exclusion>