delivery-pipeline-plugin-1.4.0

Upgraded minimum required Jenkins version to 2.164.
Minimum required Java (JVM) version: Java 8 (plugin verified to run successfully on Java 8 and Java 11).
Requirement on Java 11 SDK for delivery pipeline plugin development.

Dependencies upgraded:

• Required dependency on Pipeline: Step API plugin 2.19 (previously 2.13)
• Required dependency on Pipeline: API plugin 2.30 (previously 2.25)
• Required dependency on Pipeline: Supporting APIs plugin 3.3 (previously 2.17)

Addressed issues:
JENKINS-38062 "Create Delivery Pipeline version" errors
JENKINS-54706 Drop support for themes
JENKINS-57450 Update delivery pipeline plugin to support JDK11 build environment (current LTS Java version)
JENKINS-57451 Upgrade checkstyle to avoid external DTD access
JENKINS-58332 Fix broken promotion duration display

Release artifacts: https://repo.jenkins-ci.org/releases/se/diabol/jenkins/pipeline/delivery-pipeline-plugin/1.4.0/