如何在下面的coord xml中覆盖nominal_time属性?
<action>
<workflow>
<app-path>${app_path}/workflow</app-path>
<configuration>
<property>
<name>nominal_time</name>
<value>${coord:epochTime(coord:nominalTime(), 'false')}</value>
</property>
</configuration>
</workflow>
</action>