Ensure to change working directory for jenkins

jenkins_check_update

@@ -26,6 +26,7 @@ if [ ! -f "${JENKINS_AUTH_FILE}" ]; then
 	exit 1
 fi
 
+cd "$(dirname ${JENKINS_AUTH_FILE})" || exit
 # Verify if updates are availables for plugins
 if java -jar "${JENKINS_CLI_JAR}" -s http://127.0.0.1:8080 -auth @.jenkins.auth list-plugins | grep -i -q -- "(.*)$"
 then
@@ -35,5 +36,6 @@ else
 	rm -f "${JENKINS_PLUGIN_UPDATE_LOG}"
 	#printf '%b\n' "Nothing to do"
 fi
+cd - || exit
 
 exit 0