use external script for sending element message (due to incorrect roomId)

Jenkinsfile

+@Library('ozgcloud-libs') _
+
 pipeline {
     agent {
        node {
@@ -136,37 +138,12 @@ pipeline {
         }
         failure {
             script {
-                if (isMainBranch() || env.BRANCH_NAME == 'release') {
-                    sendFailureMessage()
-                }
+                sendMatrixMessage.sendFailureMessage(FAILED_STAGE)
             }
         }
     }
 }
 
-Void sendFailureMessage() {
-    def room = ''
-    def data = """{"msgtype":"m.text",
-                    "body":"Document-Manager: Build Failed. Stage: ${FAILED_STAGE} Build-ID: ${env.BUILD_NUMBER} Link: ${JENKINS_URL}",
-                    "format": "org.matrix.custom.html",
-                    "formatted_body":"<h3>Document-Manager: Build Failed.</h3><b>Stage:</b> ${FAILED_STAGE}<br><b>Build-ID:</b> <a href='${JENKINS_URL}'>${env.BUILD_NUMBER}</a>"}"""
-
-    if (isMainBranch()) {
-        room = "!GjqhmouBtnDbwUkAjx:matrix.ozg-sh.de"
-    }
-    else if (env.BRANCH_NAME == 'release') {
-        room = "!oWZpUGTFsxkJIYNfYg:matrix.ozg-sh.de"
-    }
-
-    sh "curl -XPOST -H 'authorization: Bearer ${getElementAccessToken()}' -d '${data}' https://matrix.ozg-sh.de/_matrix/client/v3/rooms/$room/send/m.room.message"
-}
-
-String getElementAccessToken() {
-    withCredentials([string(credentialsId: 'element-login-json', variable: 'LOGIN_JSON')]) {
-        return readJSON ( text: sh (script: '''curl -XPOST -d \"$LOGIN_JSON\" https://matrix.ozg-sh.de/_matrix/client/v3/login''', returnStdout: true)).access_token
-    }
-}
-
 String getPomVersion(String pomFile){
     def pom = readMavenPom file: pomFile
 
@@ -177,7 +154,3 @@ String getParentPomVersion(String filePath) {
     def pom = readMavenPom file: filePath
     return pom.parent.version
 }
-
-Boolean isMainBranch() {
-    return env.BRANCH_NAME == 'main'
-}