Use jenkins.baseline to reduce bom update mistakes

pom.xml

@@ -56,9 +56,9 @@ limitations under the License.
     <test.jenkins.blobstore.credential>FIXME_CREDENTIALS</test.jenkins.blobstore.credential>
 
     <jclouds.version>2.5.0</jclouds.version>
-    <!-- Depend on latest Jenkins 2.x LTS
-         See README of https://github.com/jenkinsci/plugin-pom/ -->
-    <jenkins.version>2.440.1</jenkins.version>
+    <!-- https://www.jenkins.io/doc/developer/plugin-development/choosing-jenkins-baseline/ -->
+    <jenkins.baseline>2.440</jenkins.baseline>
+    <jenkins.version>${jenkins.baseline}.1</jenkins.version>
     <gitHubRepo>jenkinsci/jclouds-plugin</gitHubRepo>
   </properties>
 
@@ -104,7 +104,7 @@ limitations under the License.
     <dependencies>
       <dependency>
         <groupId>io.jenkins.tools.bom</groupId>
-        <artifactId>bom-2.414.x</artifactId>
+        <artifactId>bom-${jenkins.baseline}.x</artifactId>
         <version>2705.vf5c48c31285b_</version>
         <scope>import</scope>
         <type>pom</type>