[#2019] Use the version of hibernate-jenkins-pipeline-helpers configured on CI

Don't configure the version in Jenkinsfile so that it's easier to upgrade next time.
See https://ci.hibernate.org/manage/configure#global-untrusted-pipeline-libraries to change the (default) version globally for all projects.

Author: yrodiere

ci/release/Jenkinsfile

@@ -9,7 +9,7 @@
 /*
  * See https://github.com/hibernate/hibernate-jenkins-pipeline-helpers
  */
-@Library('hibernate-jenkins-pipeline-helpers@1.18') _
+@Library('hibernate-jenkins-pipeline-helpers') _
 
 import org.hibernate.jenkins.pipeline.helpers.version.Version
 

ci/snapshot-publish.Jenkinsfile

@@ -1,7 +1,7 @@
 /*
  * See https://github.com/hibernate/hibernate-jenkins-pipeline-helpers
  */
-@Library('hibernate-jenkins-pipeline-helpers@1.18') _
+@Library('hibernate-jenkins-pipeline-helpers') _
 
 // Avoid running the pipeline on branch indexing
 if (currentBuild.getBuildCauses().toString().contains('BranchIndexingCause')) {