Reintroduce Docker containers for release.

Releasing requires additional tools inside the container that does the releasing process, whether to maven central or artifactory.

Resolves #1353.

Jenkinsfile

@@ -17,6 +17,21 @@ pipeline {
 	}
 
 	stages {
+		stage('Publish Eclipse Temurin (main) + gpg docker image') {
+			when {
+				changeset "ci/Dockerfile"
+			}
+			agent any
+
+			steps {
+				script {
+					def image = docker.build("${p['docker.java.build.image']}", "ci/")
+					docker.withRegistry('', "${p['dockerhub.credentials']}") {
+						image.push()
+					}
+				}
+			}
+		}
 		stage("Test: baseline (main)") {
 			agent any
 			options { timeout(time: 30, unit: 'MINUTES')}
@@ -85,7 +100,7 @@ pipeline {
 
 			steps {
 				script {
-					docker.image(p['docker.java.main.image']).inside(p['docker.java.inside.basic']) {
+					docker.image("${p['docker.java.build.image-proxy']}").inside(p['docker.java.inside.basic']) {
 						PROJECT_VERSION = sh(
 								script: "ci/version.sh",
 								returnStdout: true

ci/Dockerfile

@@ -0,0 +1,6 @@
+FROM eclipse-temurin:17.0.6_10-jdk-focal
+
+RUN apt-get update && apt-get install -y gpg
+
+RUN apt-get clean \
+ && rm -rf /var/lib/apt/lists/*

ci/pipeline.properties

@@ -6,8 +6,13 @@ java.next.tag=20-jdk-jammy
 docker.java.main.image=harbor-repo.vmware.com/dockerhub-proxy-cache/library/eclipse-temurin:${java.main.tag}
 docker.java.next.image=harbor-repo.vmware.com/dockerhub-proxy-cache/library/eclipse-temurin:${java.next.tag}
 
+# Docker container images - for release
+docker.java.build.image=springci/spring-ws-eclipse-temurin-with-gpg:${java.main.tag}
+docker.java.build.image-proxy=harbor-repo.vmware.com/dockerhub-proxy-cache/${docker.java.build.image}
+
 # Docker environment settings
 docker.java.inside.basic=-v $HOME:/tmp/jenkins-home
 
 # Credentials
 artifactory.credentials=02bd1690-b54f-4c9f-819d-a77cb7a9822c
+dockerhub.credentials=hub.docker.com-springbuildmaster