OZG-4792 Double tag on master and release, and this brnach for testing

Jenkinsfile

@@ -73,11 +73,12 @@ pipeline {
             steps {
                 script {
                     FAILED_STAGE=env.STAGE_NAME
+                    env.BUILD_TAG = generateBuildTag()
                 }
                 
                 configFileProvider([configFile(fileId: 'maven-settings', variable: 'MAVEN_SETTINGS')]) {
                     withCredentials([usernamePassword(credentialsId: 'jenkins-nexus-login', usernameVariable: 'USER', passwordVariable: 'PASSWORD')]) {
-                        sh 'mvn -s $MAVEN_SETTINGS spring-boot:build-image -DskipTests -Dmaven.wagon.http.retryHandler.count=3 -Dbuildtag=$IMAGE_TAG -Dspring-boot.build-image.publish=true -Duser=${USER} -Dpassword=${PASSWORD}'
+                        sh 'mvn -s $MAVEN_SETTINGS spring-boot:build-image -DskipTests -Dmaven.wagon.http.retryHandler.count=3 -Dimagetag=$IMAGE_TAG -Dbuildtag=${env.BUILD_TAG} -Dspring-boot.build-image.publish=true -Duser=${USER} -Dpassword=${PASSWORD}'
                     }
                 }
             }
@@ -154,14 +155,22 @@ pipeline {
 }
 
 String generateImageTag() {
+    return "${env.BRANCH_NAME}-${getPomVersion()}"
+}
+
+String generateBuildTag() {
+
+    def buildName = "docker.ozg-sh.de/administration"
+    def buildTag = buildName+":"+IMAGE_TAG
 
     if (isMasterBranch()) {
-        return "snapshot-latest"
-    }
-    else if (isReleaseBranch()) {
-        return "latest"
+        buildTag += ","+buildName+":snapshot-latest"
+    } else if (isReleaseBranch()) {
+        buildTag += ","+buildName+":latest"
+    } else if (env.BRANCH_NAME == 'OZG-4792-FixMasterBranchTagging') {
+        buildTag += ","+buildName+":doubleTagTest"
     }
-    return "${env.BRANCH_NAME}-${getPomVersion()}"
+    return buildTag
 }
 
 String getPomVersion() {

pom.xml

@@ -60,7 +60,8 @@
 				<artifactId>spring-boot-maven-plugin</artifactId>
 				<configuration>
 				<image>
-					<name>docker.ozg-sh.de/administration:${buildtag}</name>
+					<name>docker.ozg-sh.de/administration:${imagetag}</name>
+					<tags>${buildtag}</tags>
 					<publish>true</publish>
 				</image>
 				<docker>