Restore incrementals publishing (#6492)

* Restore incrementals publishing

* fix mvn install

* Exclude POM file

Co-authored-by: Tim Jacomb <21194782+timja@users.noreply.github.com>

Jenkinsfile

@@ -127,7 +127,7 @@ for (i = 0; i < buildTypes.size(); i++) {
             dir(m2repo) {
               archiveArtifacts(
                   artifacts: "**/*$changelist/*$changelist*",
-                  excludes: '**/*.lastUpdated,**/jenkins-test*/',
+                  excludes: '**/*.lastUpdated,**/jenkins-coverage*/,**/jenkins-test*/',
                   allowEmptyArchive: true, // in case we forgot to reincrementalify
                   fingerprint: true
                   )

coverage/pom.xml

@@ -9,6 +9,7 @@
   </parent>
 
   <artifactId>jenkins-coverage</artifactId>
+  <packaging>pom</packaging>
 
   <name>Jenkins coverage</name>
   <description>Compute aggregated test code coverage</description>
@@ -47,6 +48,13 @@
           <skip>true</skip>
         </configuration>
       </plugin>
+      <plugin>
+        <artifactId>maven-jar-plugin</artifactId>
+        <!-- Version specified in grandparent POM -->
+        <configuration>
+          <skipIfEmpty>true</skipIfEmpty>
+        </configuration>
+      </plugin>
     </plugins>
   </build>