jenkinsfile: fix tag generation

Change-Id: I963d7064903c485c4aabacedf73a023a09f37efc

extras/packaging/gnu-linux/Jenkinsfile

@@ -140,19 +140,22 @@ make -f extras/packaging/gnu-linux/Makefile portable-release-tarball .tarball-ve
                 sshagent(credentials: [JENKINS_SSH_KEY, DL_SSH_KEY]) {
                     echo "Publishing to git repository..."
                     script {
-                        def tagDate = sh 'date +"%Y%M%d"'
+                        def wantedTag = sh (
+                            script: "echo ${params.CHANNEL}/\$(date +\"%Y%m%d\")",
+                            returnStdout: true
+                        ).trim()
                         sh """
-                        git tag  -am ${params.CHANNEL}/${tagDate} \"Jami new ${params.CHANNEL} version\"
+                        git tag  -am \"Jami new ${params.CHANNEL} version\" ${wantedTag}
                         """
                         if (params.CHANNEL == 'stable') {
                             // Only stables releases get tarballs and a tag.
-                            sh 'git push --follow-tags'
+                            sh "git push origin --tags"
                             echo "Publishing release tarball..."
                             sh 'rsync --verbose jami*.tar.gz ' +
                                 "${REMOTE_HOST}:${REMOTE_BASE_DIR}" +
                                 "/release/tarballs/"
                         } else {
-                            sh 'git push --tags'
+                            sh "git push origin --tags"
                         }
                     }
                 }