fix Jenkinsfile Server stage

Jenkinsfile

@@ -85,9 +85,6 @@ pipeline {
 //            }
         }
         stage('Server') {
-         	when {
-                branch 'master'
-            }
             steps {
                 script {
                     FAILED_STAGE=env.STAGE_NAME
@@ -97,21 +94,23 @@ pipeline {
                         sh 'mvn --version'
                         sh "mvn -s $MAVEN_SETTINGS -pl -goofy-client clean install spring-boot:build-image -Dspring-boot.build-image.imageName=docker.ozg-sh.de/goofy:${IMAGE_TAG} -Dspring-boot.build-image.publish -Dmaven.wagon.http.retryHandler.count=3"
 
-                   		try {
-    	                    dir('alfa-service'){
-                                withSonarQubeEnv('sonarqube-ozg-sh'){
-                                    sh 'mvn -s $MAVEN_SETTINGS sonar:sonar'
-                                }
-                            }
-                            dir('alfa-xdomea'){
-                                withSonarQubeEnv('sonarqube-ozg-sh'){
-                                    sh 'mvn -s $MAVEN_SETTINGS sonar:sonar'
-                                }
-                            }
-                        }
-                        catch (Exception e) {
-                            unstable("SonarQube failed")
-                        }
+ 						if (isMasterBranch()) {
+	                   		try {
+	    	                    dir('alfa-service'){
+	                                withSonarQubeEnv('sonarqube-ozg-sh'){
+	                                    sh 'mvn -s $MAVEN_SETTINGS sonar:sonar'
+	                                }
+	                            }
+	                            dir('alfa-xdomea'){
+	                                withSonarQubeEnv('sonarqube-ozg-sh'){
+	                                    sh 'mvn -s $MAVEN_SETTINGS sonar:sonar'
+	                                }
+	                            }
+	                        }
+	                        catch (Exception e) {
+	                            unstable("SonarQube failed")
+	                        }
+	                    }
                     }
                 }
             }