jenkins: sync staging source before deploy

Jenkinsfile

@@ -130,6 +130,19 @@ PY
                 }
             }
         }
+        stage('Sync Staging Source') {
+            agent { label 'built-in' }
+            options {
+                timeout(time: 5, unit: 'MINUTES')
+            }
+            steps {
+                sh '''
+                    set -e
+                    REMOTE_CMD="cd '${STAGING_AUDIT_PROJECT_DIR}' && if [ -d .git ]; then git fetch --prune origin && git reset --hard origin/master && git rev-parse --short HEAD; else echo 'NO_GIT_REPO'; fi"
+                    sudo -n -u mandel -g www-data /srv/apps/mandel-dashboard/.venv/bin/python /srv/apps/mandel-dashboard/bin/deploy_stg_from_jenkins.py "${STAGING_AUDIT_PROJECT_NAME}" --command "$REMOTE_CMD"
+                '''
+            }
+        }
         stage('Deploy Staging') {
             steps {
                 echo 'Triggering staging deploy for mandelstudio after successful CI build.'